Tim bought 3 pens and 5 pencils at the school store. The pens and pencils
were the same price. He also bought 2 erasers for 50¢ each. He spent $5 total
at the school store. How much is a pen or pencil at the school store?

Answer:

34

Step-by-step explanation:

40 questions times 0.85 equals 34

Answer:

Imagine that scientists have just discovered a non-bird dinosaur skeleton. They want to know whether the dinosaur was closely related to birds. What features in ...

Step-by-step explanation:

Interesting question. Does that mean near the end of humanity?

Solution 1:

10^10 = 1,000,000,000

10^12 = 100,000,000,000

100,000,000,000/1,000,000,000 = 100 trees per person

Solution 2:

10^12 / 10^10  ---  10^10 / 10^10

10^2/1 = 10^2 = 100 trees per person

Answers:

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

Explanation:

For now, let's focus on system 1.

We have identical copies of "2y" in each equation, which means that if we were to subtract the equations straight down, then the y terms cancel out. That allows us to solve for x.

After doing those subtractions, we have the new equation 6x = 18 which solves to x = 3. Divide both sides by 6 to isolate x.

Once we know x, we can find out y.

7x+2y = 11

7(3)+2y = 11

21+2y = 11

2y = 11-21

2y = -10

y = -10/2

y = -5

or we can say

x+2y = -7

3+2y = -7

2y = -7-3

2y = -10

y = -10/2

y = -5

We should lead to the same y value either way. This helps confirm we have the correct x value.

Overall, the solution to system 1 is (x,y) = (3, -5)

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

Now onto system 2.

Unfortunately, we don't have identical y terms this time. But what we can do is double everything in the second equation to go from -x+y = 1 to -2x+2y = 2.

The new equivalent system is

[tex]\begin{cases}7x+2y = 11\\-2x+2y = 2\end{cases}[/tex]

Now we have the same situation as before: Subtract straight down, solve for x.

So we have 9x = 9 and that solves to x = 1.

We'll use this x to find the y value.

7x+2y = 11

7(1)+2y = 11

7+2y = 11

2y = 11-7

2y = 4

y = 4/2

y = 2

Or you could pick on the second equation

-x+y = 1

-1+y = 1

y = 1+1

y = 2

Answer:

y=2x+9

Step-by-step explanation:

I got y-2x+9 because if you add 8-1 that equals 7 and if u do 7-5 that equals 2 so y2x and then 7 Plus 2 equals 9 so it all adds up to Y=2x+9?.

Answer:

False

Step-by-step explanation:

-45x < 3

-x <  3/45

-x <  1/15                  Multiply by -1 because x is negative and remember to

                                 change all parts to its opposite.

Therefore  x  >  -1/15      

[tex]\left(\dfrac{5}{n+1}\right) \left( \dfrac{n+1}{n+3} \right)\\\\\\=\dfrac{5(n+1)}{(n+1)(n+3)} \\\\\\=\dfrac{5}{n+3}[/tex]

Answer:

$76.

Step-by-step explanation:

Answer:

They are not

Step-by-step explanation:

    We can see that 14 / 2 = 7, so we can check for the other side by dividing both sides of the ratio by 2:

15:14

\/

7.5:7 ≠ 8:7

Have a nice day!

    I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly. (ノ^∇^)

- Heather

Answer:

a. = 36km

b. Perimeter = 108km

c. Area = 486km^2

Step-by-step explanation:

Pythagoras theorem

a^2 + b^2 = c^2

27^2 + b^2 = 45^2

b^2 = 45^2 - 27^2

b^2 = 1296

b = [tex]\sqrt{1296}[/tex]

b = 36km

Perimeter

a + b + c

27 + 36 + 45 = 108

Perimeter = 108km

Area = [tex]\frac{ab}{2}[/tex]

Area = [tex]\frac{27 * 36}{2}[/tex]

Area = [tex]\frac{972}{2}[/tex]

Area = 486km^2

Answer:

1  11/24

Step-by-step explanation:

5 1/8= 41/8  

3 2/3 = 11/3

41/8 -11/3 = (41*3)/(8*3)   -(11*8)/(3*8)

              =123/24 -88/24

               = (123-88)/24

              =35/24

              =1  11/24

15 days

Step-by-step explanation:

The half-life equation is given as

[tex]m(t) = m(0)e^{-0.073t}[/tex] (1)

where m(0) is the initial mass of radioactive iodine at t = 0. To solve for the time t, let's put the exponential part on the left-hand side:

[tex]e^{-0.073t} = \dfrac{m(t)}{m(0)}[/tex]

Taking the natural logarithm of both sides to get

[tex]\ln{e^{-0.073t}} = \ln\left[\dfrac{m(t)}{m(0)}\right][/tex] (2)

Recall the following properties of logarithms:

[tex]\ln{A}^b = b\ln{A}[/tex]

[tex]\ln{e} = 1[/tex]

We can rewrite Eqn(2) as

[tex]-0.073t = \ln\left[\dfrac{m(t)}{m(0)}\right][/tex]

Solving for t, we get

[tex]t = -\dfrac{1}{0.073}\ln\left[\dfrac{m(t)}{m(0)}\right][/tex]

Since m(0) = 15 gm and m(t) = 5 gm, then the amount of time that elapses to reduce the mass down to 5 gm is

[tex]t = -\dfrac{1}{0.073}\ln\left(\dfrac{5\:\text{g}}{15\:\text{g}}\right)[/tex]

[tex]\:\:\:\:\:= 15\:\text{days}[/tex]

Answer:

x = 8, x = 10

Step-by-step explanation:

[tex]\sqrt{4x - 31}[/tex] = x - 7 ( square both sides )

4x - 31 = (x - 7)² ← expand using FOIL

4x - 31 = x² - 14x + 49 ( sub 4x - 31 from both sides )

0 = x² - 18x + 80 ← in standard form

0 = (x - 8)(x - 10) ← in factored form

Equate each factor to zero and solve for x

x - 8 = 0 ⇒ x = 8

x - 10 = 0 ⇒ x = 10

As a check

Substitute these values into the equation and if both sides are equal then they are the solutions.

x = 8

left side = [tex]\sqrt{4(8)-31 }[/tex] = [tex]\sqrt{32-31}[/tex] = [tex]\sqrt{1}[/tex] = 1

right side = 8 - 7 = 1

Then x = 8 is a solution

x = 10

left side = [tex]\sqrt{4(10)-31}[/tex] = [tex]\sqrt{40-31}[/tex] = [tex]\sqrt{9}[/tex] = 3

right side = 10 - 7 = 3

Then x = 10 is a solution

Answer:i dont know sorry

Step-by-step explanation:

An elliptical of the satellite in the field of astrodynamics is known as a

Kepler orbit.

The distance between the satellite and the Earth is; 510 km.

Reasons:

The function that represents the elliptical orbit of the satellite is presented

as follows;

[tex]\dfrac{x^2}{47,334,400} + \dfrac{y^2}{43,956,900} = 1[/tex]

The radius of the Earth, R = 6,370 km.

The equation of an ellipse is presented as follows;

[tex]\mathbf{\dfrac{(x - h)^2}{a^2} + \dfrac{(y - k)^2}{b^2}} = 1[/tex]

Where, in a horizontal ellipse;

a = The major axis (the longer axis), which gives the maximum distance

between the satellite and Earth.

b = The minor axis (the shorter axis)

By comparison, we get;

a² = 47,334,400 km²

Therefore;

a = √(47,334,400 km²) = 6,880 km.

The distance between the satellite and the surface of the Earth, d, is given

as follows;

d = a - R

Which gives;

d = 6,880 km - 6,370 km = 510 km

Distance between the satellite and the surface of the Earth, d = 510 km.

Learn more here:

https://brainly.com/question/13999216

Answer:510 KM

Step-by-step explanation:

There are no prime numbers are multiples of 8​. All the multiples of 8 are divided by 2.

Prime numbers are whole numbers larger than one with only one element the number itself. Prime numbers can only be divided by the number 1 or by themselves.

All the terms that come in the table of 8 are multiples of 8.

8, 16, 24, 32, 40, 48, 56, 64, 72, and 80 are the multiples of 8. There are no prime numbers are multiples of 8​.

Hence there is no prime numbers multiples of 8​.

To learn more about the prime number refer to the link;

https://brainly.com/question/9315685

Answer:

X-intercept: [tex](\frac{14}{3}, 0)[/tex].

Y-intercept: (0, 7) ⇒ Option B.

Step-by-step explanation:

I'm not certain whether the question asks for either the x-intercept or the y-intercept, but I will provide the answers for both since none of the given options matches the coordinates of the x-intercept.  

The x-intercept is the point on the graph where it crosses the x-axis, with coordinates of (a, 0).  The x-intercept is the value of x when y = 0.

Given the linear equation in standard form, 3x + 2y = 14, set y = 0 to solve for the x-intercept:

3x + 2y = 14

3x + 2(0) = 14

3x + 0 = 14

3x = 14

Divide both sides by 3 to solve for x:

[tex]\frac{3x}{3} = \frac{14}{3}[/tex]

[tex]x = \frac{14}{3}[/tex]

Therefore, the x-intercept is [tex](\frac{14}{3}, 0)[/tex].   None of the given option matches the value of the x-intercept.

The y-intercept is the point on the graph where it crosses the y-axis, and has coordinates of (0, b). It is the value of y when x = 0.

Set x = 0, and substitute into the given equation.

3x + 2y = 14

3(0) + 2y = 14

0 + 2y = 14

2y = 14

Divide both sides by 2 to solve for y:

[tex]\frac{2y}{2} = \frac{14}{2}[/tex]

y = 7

Therefore, the y-intercept is (0, 7), which matches Option B.

Answer:

3 hours

144 bulbs

Step-by-step explanation:

33t + 45 = 36t + 36

Subtract 33t from both sides

45 = 3t + 36

subtract 36 fromboth sides

9 = 3t

divideboth sides by 3

3 = t

3 hours

How many bulbs will that be?

33(3) + 45

99 + 45

144

Answer:

ASA congruence

Step-by-step explanation:

here two angles and in between side are equal for these two triangles

Answer:

12

Step-by-step explanation:

12x - 4 = 10x + 20

2x - 4 = 20

2x = 24

x = 12

Check the picture below.

Answer:

1: How much longer did he run than walk.

2: Subtraction

3: 1/8 hour

Step-by-step explanation:

1: The last sentence says what is being asked.

2: We want to see how much longer something is so it is subtraction.

3: 3/4 = 6/8    7/8 - 6/8 = 1/8

[tex]LHS \\ = 8 + 7 - {2}^{2} \\ = 8 + 7 - 4 \\ = 15 - 4 \\ = 11[/tex]

[tex]RHS \\ = {3}^{2} + 2 \\ = 9 + 2 \\ 11[/tex]

So, LHS = RHS

=

Hope it helps.

Do comment if you have any query.

Answer:

Below!

Step-by-step explanation:

Let's try the 'equal' sign for this equation.

Remember, when it comes to simplifying, exponents come first. This means that we need to simplify the exponents first.

Since the LHS and the RHS are equal, the 'equal' sign will fit into the equation. Hence, this is proven as true. Let's try the 'not equal' sign.

Now, this is a definite false. The 'not equal' sign is used when two values are not equal to each other, however, in this situation, 11 does equal 11. In between them is a 'not equal' sign. Hence, this is proven false.

We can conclude that the sign you are looking for is an 'equal' sign.

Hoped this helped.

[tex]BrainiacUser1357[/tex]

Step-by-step explanation:

13.

oh, come on !

you never had and solved the situation "one piece costs that much, how much will be 2 or 5 or 10 of them ?"

it is a simple multiplication.

and hence the answer B.

the first hint is already in the table with 1 pizza costing $5.25.

2 pizzas are then 2×$5.25, 3 pizzas 3×$5.25, ...

so, the cost c = number of pizzas × $5.25

or short

c = p×5.25 or 5.25p

14.

the domain is the interval or set of valid values for the input variable (x) of a function/relation.

and the range is the interval or set of valid values for the result variable (y) of a function/relation.

so, the domain is the set {-3, -1, 0, 1, 3}.

and the range is the set {-4, 0, 2, 4}.

In mathematics, a function is a binary relation between two intervals or sets that associates each element of the first interval/set (domain) to exactly one element of the second interval/set (range).

and that's what is done here.

it is a function.

each value of x is associated exactly with 1 result value of y.

a y value can be associated with more than one x value - no problem.

but no x value can have more than one associated y value - otherwise that would break the principle of a function.

Answer:

d wound be the only answer I think

In what context? Do you mean calculus If you are talking about graphing on a graph plane it would be the two accelerates on the x axis so (left or right) and then the 1.5 accelerates on the y axis so 1.5 on the y axis would be one and halfway to the 2 mark on the y axis so in the middle of 1 to 2 on the y axis the y axis goes (up and down)

Answer:

6,240

Step-by-step explanation:

You start off with 5200, if she earns 4% each year for the next 5 years, she would earn a total of 20% more than what she had now.

You would multiply 5,200 by 1.20 Which equals the answer (above)

Answer:

D. 140

Step-by-step explanation:

4 / 80 = 20

20 * 7 = 140

therefore, 140 is the answer

Answer:

140

Step-by-step explanation:

Answer:

510

Step-by-step explanation:

10/100 = 51

10*10/100 = 51*10

100/100 = 510