How do
you
create equations and use them to solve
problems?

Answers

Answer 1

Answer:

define the unknown quantity as =variable. Then use the given info to write down an equation in terms of the unknown quantity. At the end, solve the equation for the unknown.

Answer 2
Define the unknown quantity as a variable

Related Questions

Max is designing a hot tub for a local spa.

He wants the hot tub to have a diameter of 90 inches, what is the approximate area required for the installation of the hot tub? (Use 3.14 for.)

Answers

The area of the hot tub to be installed for local spa is 6358.5 in².

What is defined as the circle?A circle is a round figure with no corners as well as edges.A circle is defined in geometry as a closed, double curved shape.The center of the a circle is the point in a circle where all distances to the circle's points are equal. This distance is known as the circle's radius.The diameter of a circle is a line segment that passes through center of a circle and has its endpoints just on circle.Diameter = 2 × radius

For the given question;

The diameter of the hot tub to be installed for local spa is 90 inches.

Then, radius is 90/2 = 45 inches.

The area of the circle is;

Area = πr²

Where,  π = 3.14

Put the values;

Area = 3.14×45²

Area = 6358.5

Thus, the area of the hot tub to be installed for local spa is 6358.5 in².

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The nurse is assessing a client’s lymphatic system. For which enlarged node should the nurse suspect that the client has a blockage within the right lymphatic duct?.

Answers

The enlarged node that the nurse should suspect that the client has a blockage within the right lymphatic duct is the right cervical node

What is the lymphatic system?

A network of tissues, blood arteries, and organs called the lymphatic system collaborates to transport lymph, a colorless, watery fluid, back into your circulatory system. Every day, your body's arteries, smaller arteriole blood vessels, and capillaries circulate about 20 liters of plasma.

The right lymphatic duct receives drainage from the right cervical node. The thoracic duct receives drainage from the superficial popliteal, superficial inguinal, and lumbar nodes. The sides and back of the neck include the cervical lymph nodes.

Typically, these glands are incredibly tiny. A lymph node, however, is swollen if its diameter is higher than 1 centimeter. Deep inside the neck, the cervical lymph nodes are located.

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The measure of an acute angle is represented by (3x + 12)°. Which is not a possible value for x?
A 26
B 21
C) 23
D25

Answers

a)26 is not a possible value for x as the angle becomes a right angle and doesn't remain acute

An acute angle is one whose measure is less than 90 degrees. The given acute angle in the question is represented by (3x+12)°

if x=26 then the angle is 90°

if x= 21 then the angle is 75°

if x=23 then the angle is 81°

if x=25 then the angle is 87°

∴26 cannot be a possible value for x as the angle becomes 90 degrees (right angle) and doesn't remain acute any longer.

Thus the correct answer is option a)26

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A car park charges £1.20 to each car entering.
The payment station only accepts £1 coins and 20p coins.
Here are the coins collected from the payment station on a particular day:
Number of £1 coins
176
Number of 20p coins
320
Assuming each driver paid the exact amount due on that day, work out the
percentage of drivers that paid with six 20p coins.
Optional working
+
Answer:

Answers

Answer: 12%

Step-by-step explanation:

12%

Explanation:

If has 176 £1 coins then 176 drivers paid £1 and 20 p coins.

The rest of the driver paid with 20 p coins.

So the number of 20 p coins is:

320 - 176 = 144

Since £1 and 20 p need 6 coins of 20 p, the number of drivers who paid only for 20 p coins is:

144 / 6 = 24

The total number of drivers is:

176 + 24 = 200

The percentage of drivers who paid only with coins id 20 p is:

24 / 200 • 100% =

0.12 • 100% = 12%

help meeeeeeeeeeee pleaseeeeeeeeeeeeee!!

Answers

I’m guessing square inches

A car rental service charges an initial fee of $250 and 25$ for every hour using the car. If a customers bill totals $1,275 then how long did they rent the car for?​

Answers

41 is the answer !! Yipeeeee
Answer:  41 hours

======================================================

Explanation:

x = number of hours

y = total cost

The equation is y = 25x+250 since 250 is the initial cost, aka y intercept, and 25 is the slope telling us how much the cost goes up per hour (aka rate of change).

I recommend making a table of values to help see how/why that equation works out.

Plug in y = 1275 and isolate x.

y = 25x+250

1275 = 25x+250

1275-250 = 25x

1025 = 25x

25x = 1025

x = 1025/25

x = 41 hours

----------------

Check:

If the customer rents the car for 41 hours, then they pay 25*41 = 1025 dollars on top of the initial fee of $250.

The total cost is therefore 1025+250 = 1275 dollars to confirm the answer.

----------------

Extra info:

41 hours = 24 hours + 17 hours = 1 day + 17 hours

41 hours = 41/24 = 1.70833 days approximately

Please help , I need help thanks
these are the questions there are five , I need this today
I will give out brainlist

Answers

The solution to the inequality problem is represent by the graph attached below.

Graph of Inequalities

To solve this problem we simply need to use a graphing a calculator to plot the graph of the two inequalities. The points of intersection represents the solution of the graph.

The broken purple line represents the first inequality and the second straight line represents the second inequality.

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“If the sum of two angles is 180 then the angles are supplementary

Answers

If the sum of two angles is 180 then the angles are supplementary.This is true.

What are supplementary angles?

Supplementary angles are those that total 180 degrees. Angles 130° and 50°, for example, are supplementary angles since the sum of 130° and 50° equals 180°.

If the total of two angles is 180 degrees, they are considered to be supplementary angles since they form a linear angle when combined. If the total of two angles is 90 degrees, they are considered to be complimentary angles since they produce a right angle when combined.

If two angles add up to 180 degrees, they are considered to be supplementary angles in geometry. For example, if A + B = 180°, A and B are referred to as supplementary angles. When supplementary angles are combined, they always yield a straight angle (180 degrees).

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There is a line that includes the point (1, – 2) and has a slope of 10. What is its equation in point-slope form?

Answers

The equation of line in point - slope form will be;

⇒ y + 2 = 10 (x - 1)

What is Equation of line?

The equation of line in point-slope form passing through the points

(x₁ , y₁) and (x₂, y₂) with slope m is defined as;

⇒ y - y₁ = m (x - x₁)

Where, m = (y₂ - y₁) / (x₂ - x₁)

Given that;

The point on the line = (1, -2)

And, The slope of the line = 10

Now,

Since, The equation of line in point-slope form is;

⇒ y - y₁ = m (x - x₁)

Where, (x₁ , y₁) is the point on the line and m is slope of the line.

Hence, The equation of line in point-slope form passing through the points (1, -2)  with slope 10 is;

⇒ y - y₁ = m (x - x₁)

⇒ y - (-2) = 10 (x - 1)

⇒ y + 2 = 10x - 10

⇒ y = 10x - 10 - 2

⇒ y = 10x - 12

Thus, The equation of line in point - slope form will be;

⇒ y + 2 = 10 (x - 1)

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I keep getting the wring answer. I don’t know what I’m doing wrong.

Answers

we have the expression

[tex]y=x^2+x-4[/tex]

Remember that

[tex]i^2=-1[/tex]

Evaluate

For x=2i

substitute

[tex]y=(2i)^2+2i-4[/tex][tex]y=4i^2+2i-4[/tex][tex]\begin{gathered} y=4(-1)+2i-4_{} \\ y=-4+2i-4 \\ y=-8+2i \end{gathered}[/tex]

What are the sum of all the factors of 50 which are between 1 and 50. A. 42B. 2550C. 92D. 15

Answers

Factors of 50 are the numbers which on dividing 50 leave no remainder. 50 is a composite number, therefore, it has more than 2 factors.

We can get the factors of 50 by Prime Factorization. We can draw a factor tree to get the prime factors of 50 as shown below:

Therefore, the prime factors are:

[tex]2,5,5[/tex]

Hence, the other factors are:

[tex]\begin{gathered} 2\times5=10 \\ 5\times5=25 \end{gathered}[/tex]

Therefore, the factors of 50, including 1 and 50, are:

[tex]1,2,5,10,25,50[/tex]

The question asks to sum all the factors between 1 and 50. This means that 1 and 50 are not included in the sum.

Therefore, the sum will be:

[tex]\Rightarrow2+5+10+25=42[/tex]

The correct option is OPTION A.

4. last year nina invested $6,000. she put some of it in a cd the paid 4% simple interest, and she put the rest of it in a savings account that earned 2.5% simple interest. at the end of the year she earned a total of $204 interest. how much did she invest in each account? assume there were no other deposits or withdrawals.

Answers

She invested $2,400 in the 2.5% account and $3,600 in the 4% simple interest account

Here, we want to know the amount of money invested in each account

Let the amount invested in the 4% simple interest account be $x ----> (a)

While the amount invested in the 2.5% account be $y -------->(b)

So mathematically;

Both the interests are added to get total interest

x + y = 6,000 ••••••(i)

Let’s now evaluate the interest

for the 4% account , interest = 4/100 * x = 4x/100

For the 2.5% account, interest = 2.5/100 * y= 2.5y/100

The addition of both  interests gives the total simple interest;

4x/100 + 2.5y/100 = 204

Multiply through by 100

4x + 2.5y = 20,400 •••••••(ii)

From i, x = 6,000 - y

Putting this into equation ii

4(6,000-y) + 2.5y = 20,400

24,000 - 4y + 2.5y = 20,400

24,000-20,400 = 4y - 2.5y

1.5y = 3,600

y = 3,600/1.5

y = $2,400

Recalling it again,

x = 6000 - y

x = 6,000 - 2,400

x = $3,600

Therefore, Nina invested $2,400 in the 2.5% account and $3,600 in the 4% simple interest account

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Write a two-column proof

Answers

The angles ∠4 and ∠6  are found to be supplement angles.

What are termed as the supplement angles?Supplementary angles are the ones that total 180 degrees. Angles 130° and 50°, for example, are supplementary angles since the sum of 130° and 50° equals 180°. Complementary angles, on the other hand, add up to 90 degrees. When the 2 supplementary angles are joined together, they create both a straight line and an angle.It should be noted, however, that the two supplementary angles are not required to be adjacent to each other. As a result, any two angles could be supplementary if their total amount is equal to 180°.

For the given question;

∠5 ≅ ∠6 ( both are congruent means equal)

As, ∠4 and ∠5 are forming on the straight line. Thus,

∠4 + ∠5 = 180 (linear pair)

But, ∠5 ≅ ∠6 , replacing ∠5 with ∠6 .

∠4 + ∠6 = 180 supplement angles.

Thus, ∠4 and ∠6 are found to be supplement angles.

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6+3x^4+7x^5+7x^2 it’s polynomials

Answers

The given polynomial 6+3x⁴ +7x⁵ +7x² is a quadrinomial.

What is Quadronomial?An expression that consists of variables, constants, and exponents and is combined using mathematical operations like addition, subtraction, multiplication, and division is referred to as a polynomial (No division operation by a variable).One-term polynomials are referred to as monomials, two-term polynomials as binomials, and three-term polynomials as trinomials depending on the number of terms with nonzero coefficients. A four-term polynomial is occasionally referred to as a "quadrinomial."

So, 6+3x⁴ +7x⁵ +7x²:

We can observe that the given polynomials have 4 terms, and a polynomial with 4 terms is known as a quadrinomial.Hence, the given expression is quadrinomial.

Therefore, the given polynomial 6+3x⁴ +7x⁵ +7x² is a quadrinomial.

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Write the equation of each parabola in vertex form

Answers

Answer: 9. y=[tex](x+4)^2-3[/tex]

10. y=[tex]-(x-5)^2+5[/tex]

11. y=[tex](x-2)^2+1[/tex]

12. y=[tex]x^2-3[/tex]  or y=[tex](x-0)^2-3[/tex]

Step-by-step explanation:

find the length of the arc shown in red. Leave your answer in terms of pie

Answers

EXPLANATION

Given the circle, we can see the following facts:

Diameter= 24 ft ----> radius= 12 ft

Total arc length = 360°

The arc of a semi-circle is equal to 360/2 = 180 degrees

The red labeled arc is given by the difference between 360, the other 60 degrees and the semi-circle,

360° - 180° - 60° = 120°

So, representing this as a radian form:

[tex]\text{arc length = 2}\cdot\pi\cdot r\cdot(\frac{\theta}{360})[/tex][tex]\text{arc length = 2}\cdot\pi\cdot12\cdot(\frac{120}{360})[/tex]

Multiplying terms:

[tex]\text{arc length = 24}\cdot\pi\cdot\frac{1}{3}[/tex]

Simplifying:

[tex]\text{arc length= 8}\cdot\pi[/tex]

So, the answer is 8π ft

Trina wants to hang-glide at the same number of meters above sea level as she scuba-dived below sea level. Will she fly higher than Jessie did? Explain

Answers

Trina is closer to the surface of the ocean. She will not fly higher than Jessie did.

Consider the provided information.

The distance is the absolute value of a number.

Part (A) : It is given that Trina went scuba diving and reached an elevation of -85.5 meters, which is below sea level.

That means the distance she covers is: |-85.5| = 85.5 meters

Thus Trina covers 85.5 meters.

Jessie went hang gliding and reached 87.9 meters which is above sea level.

That means the distance she covers is: |87.9| = 87.9 meters

We know that 85.5 < 87.9

So, we can say that Trina is closer to the surface of the ocean as she covers less distance.

Part (B) : Trina wants to hang glide at the same number of meters above sea level as she scuba dived below sea level.

That means she will hang the glide at a height of 85.5 meters.

As we know 85.5 < 87.9

Thus, she will not fly higher than Jessie.

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PLEASEEEE HELPPP!!!!

Answers

1. x=11
Height=4
Área=25

2. x=35
Hypotenuse= 39
Area=296

Hope this helps!

Describe all the x-values within or including a distance of the given value.
(Enter your answer using interval notation.)
Distance of 2 units from the number 7

Answers

The range of values, in interval notation is [-6,14] .

What is interval notation in math?

Continuous sets of real numbers can be represented by the integers that bound them using interval notation. When written, intervals resemble ordered pairs in several ways. They don't necessarily indicate a particular point, though. They are intended to serve as a shortened manner of expressing an inequality or system of inequalities.

the values with a distance of 10 units from 4.

Maximum value to the right, 10 units from 4 is 4+10 = 14

Maximum value to the left, 10 units from 4 is 4 - 10 = -6

So, all the range of values, in interval notation is [-6,14]

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a length of black steel pipe is 21'-0" long. how much if the length remains of two pieces 7'-9 5/8" are cut from the length?

Answers

A mixed fraction is one that is represented by both its quotient and remainder. A mixed fraction is, for instance, 9 5/8, where 9 is the quotient and 5 is the remainder.

Remain length = 13.2' = 13' 2 2/5 ".

What is a mixed fraction?The quotient and remainder of a fraction are used to represent it, making it a mixed fraction. For instance, 2 1/3, where 2 is the quotient and 1 is the remainder, is a mixed fraction. A mixed fraction is a combination of a whole number and a recognized fraction.Subtract the denominator from the numerator. The quotient's whole number component should be written down. Write the leftover amount on top of the original denominator.A mixed number is said to be in its simplest form if its fractional part's highest common factor, or HCF, is 1. When mixed numbers are simplified, the fraction's value doesn't change. We can assert that the actual mixed number and the simplified mixed number are fractions of the same size.

Length of black steel pipe is 21'-0".

7' 9 5/8" =7.8 '

Remain length = 13.2' = 13' 2 2/5 ".

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Change 36 inches into feet given the fact that 1 foot = 12 inches.

Answers

Answer:  3 feet

===============================================

Work Shown:

1 foot = 12 inches

3*1 foot = 3*12 inches

3 feet = 36 inches

I multiplied both sides by 3 so that the "12" turns into "36".

Answer:3 feet

36/12=3

3x12=36

so 36 inches= 3 feet

hope it helps

what is an equation of the line that passes through the points (-4, 5) and (-4, -2)

Answers

Answer: no equation can pass through those points

Step-by-step explanation:

the x value -4 has two y values, 5 and -2. a function needs at most 1 y value to be considered a function.

line L passes through (3,5) and is parallel to y = 6x-2. Find the equation of line L

Answers

Answer:

y = 6m - 13

Step-by-step explanation:

Parallel lines have the same slope.  The slope in the equation y = 6x -2 is 6.

To write an equation in the slope intercept form, we need a slope and a y-intercept.  We have the slope, we need to find the y-intercept.

To find the y intercept, we need a slope, and x on the line and a y on the line.  The point (3,5) gives us the x and the y.

slope = 6

x = 3

y = 5

y = mx + b  plug in what we know and solve for b

5 = 6(3) + b

5 = 18 + b  Subtract 18 from both sides of the equation

-13 = b

y = mx  + b

y = 6m - 13

A custodian must move a shipment of books from the first floor to the sixth floor. The elevators weight limit is 900 pounds. If the custodian weighs 160 pounds and each box of books weighs 37 pounds , find the maximum number of boxes the custodian can move on the elevator at one time

Answers

Step-by-step explanation:

160 + 37x <= 900

37x <= 740

x <= 20

the custodian can move max. 20 boxes on the elevator at one time.

if he/she is always riding with the boxes.

if the custodian would climb the stairs and let the books ride alone, there could be

37x <= 900

x <= 900/37 = 24.32432432 ≈ 24

boxes on the elevator at one time.

The musical note e can be modeled by the function, y = asin(1320Ï€x), where a = 1 and x is the time in seconds. playing note e on your computer, you notice that it is not loud enough to be heard across the room. what change can you make to the function to make note e louder than the original? let a < 0. let a > 0. let a > 0 and a < 1. let a > 1 or a < â€"1.

Answers

The change that increases the loudness is a > 1

How to determine the change?

From the question, the equation of the function that represents the musical note is given as

y = a sin(1320πx)

Where

a = 1 i.e. the amplitudex represents the time

In sound, the sound loudness is directly proportional to the amplitude.

This means that an increment in the amplitude, would cause the note to become louder

This change is represented as a > 1

This is so because a represents the amplitude, and the initial value is 1

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A cyclists speed is 1.5 times faster than a walkers speed. they simultaneously start moving in the same direction from the same point and, after 1.5 hours, the distance between them is 12.5 miles. what are their speeds?

Answers

Answer:

The biker's pace is 25 miles per hour and the walker's speed is 50/3 miles per hour.

Answer:The speed of the walker is 16.67 miles per hour.

The speed of the cyclist is 25 miles per hour.

How to calculate the value?

Let the speed of a walker = x

Biker's speed = 1.5x

Their relative speed will be:

= 1.5x - x = 0.5x

Distance between them = 12.5 miles

Time taken = 1.5 hours.

It should be noted that distance will be:

= Speed × Time

12.5 = 1.5 × 0.5x

Divide through to get x

12.5 = 0.75x

x = 16.67 miles per hour.

Speed of cyclist = 16.67 × 1.5 = 25 miles per hour.

PLEASE SOLVE!
x+146=546
I tried but can't get it

Answers

[tex]x+146=546[/tex]

Subtract 146 from both sides:

[tex]x+146-146=546-146\\[/tex]

[tex]x=400[/tex]

Answer:

x = 400

Step-by-step explanation:

x + 146 = 546

We need to subtract 146 on both sides.

146 - 146 is equal to 0 so we cancel out. 546 - 146 is equal to 400.

So now x is alone and we have our answer.

x = 400

On a cold January day, Klara noticed that the temperature dropped 21 degrees over the course of the day to –9°C. Write and solve an equation to determine what the temperature was at the beginning of the day.

Answers

x = 21 - 9
x = 12
The temperature at the beginning of the day was 12* C

in a rectangle, one side is 3 times as long as the other. Now the longest side is extended by 4m. Then the area will be 96 square meters larger. How long were the original sides?

Answers

The length of the original sides of the rectangle are 72m and 24m.

What is Area of a Rectangle?

The area of a rectangle formula is used to calculate the area occupied by the rectangle within its boundaries. A rectangle's area is calculated by multiplying its length and breadth.

Given:

One side is 3 times as long as the other in a rectangle.

Let the length of the rectangle be 3x and the breadth of the rectangle be x.

Area of original rectangle = length × breadth

                             = 3x² m²

Now, the longest side is extended by 4m.

Length of rectangle = 3x + 4

Area of rectangle = length × breadth

                             =  x(3x + 4) m²

It is given that this area will be 96 square meters larger than the former.

So, x(3x + 4) - 3x² = 96

⇒ 3x² + 4x - 3x² = 96

⇒ 4x = 96

⇒ x = 24 m

Original length of the rectangle = 3x = 3×24 = 72m

Therefore, the original length of the rectangle is 72m and the original breadth of the rectangle is 24m.

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1.2x10-8 x 4.0×10-3
Scientific Notation​

Answers

Answer:

−3.11×10^2

Step-by-step explanation:

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