Answer:
B 13/2
Step-by-step explanation:
2x² + 7x - 15 = 0
First we want to find the two solutions
We can do this by using the quadratic formula
Quadratic formula:
[tex] \frac{- b + or - \sqrt{b {}^{2} - 4(a)(c)} }{2(a)} [/tex]
Where the values of a,b and c are derived from the equation.
The equation is put in ax² + bx + c = 0 form
2x² + 7x - 15 = 0
so a = 2, b = 7 and c = - 15
We now plug these values into the quadratic formula
(-(7) + or - √7² - 4(2)(-15) ) / 2(2)
first solution: -(7) + √7² - 4(2)(-15) ) / 2(2)
remove parenthesis on 7
(-7 + √7² - 4(2)(-15) ) /2(2)
Apply exponents 7²
(-7 + √49 - 4(2)(-15) ) /2(2)
Multiply -4,2 and -15
(-7 + √49 + 120 ) / 2(2)
add 49 and 120
(-7 + √ 169 ) / 2(2)
Take square root of 169
(-7 + 13 ) / 2(2)
add 13 and -7
6/2(2)
multiply 2 and 2
= 6/4
The first solution is 6/4 or 1.5
Now the second solution: -(7) - √7² - 4(2)(-15) ) / 2(2)
For the second solution we basically go through the same steps as for finding the first solution, the only difference is instead of adding -b and √b² - 4(a)(c) we are subtracting.
So we would have ( -7 - 13 ) / 2(2) instead of (-7+13)/2(2)
So second solution: ( -7 - 13 ) / 2(2)
subtract 13 from -7
-20/2(2)
multiply 2 and 2
-20/4
divide
The second solution is -5
Now that we have found the solutions we want to find r - s if r and s are the solutions to the equation and that r > s
The two solutions are 6/4 and -5.
6/4 > -5 so we know that r must equal 6/4 and s must equal -5 because r has to be greater than s
So if r = 6/4 and s = -5
Then r - s = 6/4 - (-5) = 6/4 + 5 = 13/2
So the answer is B. 13/2
Shonda met with her son's English class teacher at a parent conference. The teacher told Shonda that her son got 78, 89, 63 and 82 on his first four tests. There is one test left and he needs to increase his average to 80% to get a B in the class. What does he need to get on the last test to have an 80% average?
Answer:
In order for him to get a B, he would need to get a 88 on his next test.
I need help with this ASAP It will give you 55 points!!!!!!!
A small publishing company is planning to publish a new book. The production costs will include one-time fixed costs (such as editing) and variable costs (such as printing). The one-time fixed costs will total $26,780 . The variable costs will be $9 per book. The publisher will sell the finished product to bookstores at a price of $22 per book. How many books must the publisher produce and sell so that the production costs will equal the money from sales?
Answer: 2,435
Step-by-step explanation:
trust
A certain blueprint shows two fences. Fence A is 1 1/5 yards long but is 1 4/5 inches long on the blueprint. What is the unit rate for inches per yard on this blueprint? If the fence B is 4 yards long, how long is fence B on the blueprint?
Answer:
Q1: 3/72
Q2: 6 inches
Step-by-step explanation:
What is the unit rate for inches per yard on this blueprint?
First convert 1 1/5 yards to inches, so that becomes 216/5 inches.
To keep things consistent, let's convert the 1 4/5 inches to an improper fraction: 9/5 inches.
The question asks for inches per yard, so we substitute in the values:
[tex]\frac{\frac{9}{5} }{\frac{216}{5} }[/tex]
and simplify: 3/72
If fence B is 4 yards long, how long is fence B on the blueprint?
Convert 4 yards to inches (to comply to the ratio above): 144 inches
The ratio is inches to yards, so substitute in the value:
[tex]\frac{3}{72} = \frac{x}{144}[/tex]
and solve: 6 inches
solve for c.
c + 3/8 = 1 1/3
Enter your answer as a fraction in simplest form.
Answer:
Let's solve your equation step-by-step.
c+
3
8
=1
1
3
Step 1: Simplify both sides of the equation.
c+
3
8
=
4
3
Step 2: Subtract 3/8 from both sides.
c+
3
8
−
3
8
=
4
3
−
3
8
c=
23
24
Answer:
c=
23
24
PLEASE HELP!!! WORTH 50 PTS
6.7 Problem 12
A given bacteria culture initially contains 2500 bacteria and doubles every half hour. The number of bacteria p at a given time t is given by the formula p(t)=2500ekt for some constant k. (You will need to find k to answer the following.)
(a) Find the size of the bacterial population after 20 minutes.
(b) Find the size of the bacterial population after 9 hours.
Answer:
I think it is 392=but am not sure
Four friends are creating posters for their presentations, which will be delivered in different locations. Which person should create the largest posters
Answer:
Lindsey, who is delivering her speech in a large auditorium
Step-by-step explanation:
Jin, who is delivering her speech to a small group sitting around a table
Lindsey, who is delivering her speech in a large auditorium
Luke, who is delivering his speech in a typical classroom
Jordan, who is delivering his speech in a small meeting room
How to solve absolute value inequalities.
Answer:
I cant even see anything can you reupload your answer, please?
Step-by-step explanation:
I’m not good at stuff like this but I would give my life if someone can help me please
Answer:
I want so much to help u, but I can't right now. I will come back tomorrow and answer it.
what is the simplest form of 32/40
Answer:
4/5
Step-by-step explanation:
Answer:
4/5 or as in decimals, 0.8
Step-by-step explanation:
32/8=4
40/8=5
One box is placed on a scale. A second box that is known to weigh 10 pounds less than the first box is stacked on top of the first box.
Together, the boxes weigh 48 pounds.
If w represents the weight of the first box placed on the scale, write a problem ?
Let w represents the weight of the first box placed on the scale and y represent the weight of the second box.
The second box weigh 10 pounds less than the first box. Hence:
y = w - 10
-w + y = -10 (1)
The two boxes weigh 48 pounds. hence:
w + y = 48 (2)
Solving both equations gives:
w = 29, y = 19
The first box weighs 29 pounds while the second box weighs 19 pounds.
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if n < 0
√(n^2) = ???
thank youuuuu
Answer:
-n
Step-by-step explanation:
The symbol √ means the principal square root.
The principal square root is always non-negative.
For example, even though the number 25 has two square roots, -5 and 5, since both (-5)² and (5)² equal 25, when you express the square root using the square root symbol, then √25 = 5, and not -5, since √25 means the principal square root of 25, and as a principal square root, it must be a non-negative number.
If n < 0, then you are dealing with negative numbers.
Once you square n to get n², n² is a positive number.
Then the square root of n², expressed with the square root symbol as √(n²) must be positive, so it equals -n.
Example:
Let n = -8.
Then n² = (-8)² = 64.
√(64) = 8
Compare 8 to -8. 8 is -(-8), just like we get -n.
Answer: -n
Which graph shows the lowest cost per square foot for a new home?
Answer:
the bottom right
Step-by-step explanation:
Josephine was charged $7.20 for a long distance call that lasted 1.5 hours. What was the cost per hour for her long distance call?
Based on the information given, the cost per hour for her long-distance call will be $4.80.
Amount that was charged for the call = $7.20
Number of hours used = 1.5 hours
The cost per hour for her long-distance call will be:
= Amount that was charged for the call / Number of hours used
= 7.20 / 1.5
= $4.80
In conclusion, the cost is $4.80.
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A watt is the basic unit measurement of electrical power. Suppose you are running the air conditioner, the washing machine, the clothing dryer, two computers, four light bulbs, the refrigerator, and two televisions Use the chart at the right and calculate how much wattage you might need in this situation. Show your k = write an inequality that shows what the available wattage must be greater than
Considerations based on the wattage of the available appliances are required when designing for the electricity.
The required wattage inequality is; Available wattage > 10,460 WattsReasons:
The items used and the possible power consumption obtained from a similar are as follows;
Appliance [tex]{}[/tex] Average power (Watts)
One air conditioner; [tex]{}[/tex] 3,500
Washing machine; [tex]{}[/tex] 500
Clothing dryer; [tex]{}[/tex] 5,000
Computers × 2; [tex]{}[/tex] 70 × 2 = 140
Light bulbs × 4; [tex]{}[/tex] 60 × 4 = 240
Refrigerator; [tex]{}[/tex] 600
Television × 2; [tex]{}[/tex] 240 × 2 = 480
The power, P, in watts that might be needed is found as follows;
Power, P = 3,500 + 500 + 5,000 + 140 + 240 + 600 + 480 = 10,460
The electric power in watts that might be needed, P = 10,460 Watts
Therefore;
The available wattage must be greater than 10,460 Watts
The inequality is; Available wattage > 10,460 Watts
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The sizes of the angles in degrees of e triangles are.
2x+7
2x
X+18
Use this information to write down an equation in terms of x
PLEASE HELP WILL MARK BRAINLIEST
Find the average rate of change for the function f(x) = 3^x + 4
Using the intervals of x=2 to x=5
Show ALL your work to receive credit
Answer:
78
Step-by-step explanation:
You use the formula
[tex] \frac{f(b) - f(a)}{b - a} [/tex]
with a=2 and b=5 plug it in to the formula
[tex] \frac{f(5) - f(2)}{5 - 2} [/tex]
find the values
[tex]f(5) = {3}^{5} + 4 = 247 [/tex]
[tex]f(2) = {3}^{2 } + 4 = 13[/tex]
put it all together
[tex] \frac{247 - 13}{5 - 2} = \frac{234}{3} = 78[/tex]
Functions or Not a Function? Explain?
Answer:
function
Step-by-step explanation:
To be a function, each value of the x-coordinate can be used only once. In other words, all x-coordinates must be different.
Here, the x-coordinates are all different, so it is a function.
what part of 3 dollars are 25 nickels
Answer:
25 nickles are 5/12ths of a dollar
Step-by-step explanation:
25*5=125, or $1.25. Now we make this a fraction, we get 1.25/3, or 5/12
The 25 nickels are the 5/12 part of the 3 dollars.
What is Algebra?Algebra is the study of abstract symbols, while logic is the manipulation of all those ideas.
The acronym PEMDAS stands for Parenthesis, Exponent, Multiplication, Division, Addition, and Subtraction. This approach is used to answer the problem correctly and completely.
We know that 1 nickel = 0.05 dollars.
Then the number of dollars in 25 nickels will be given as,
⇒ 25 x 0.05
⇒ $1.25
Divide the number 1.25 by 3. Then we have
⇒ 1.25 / 3
⇒ 5 / 12
The 25 nickels are the 5/12 part of the 3 dollars.
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Soooo I’m kinda confuzzled, I have trouble simplifying decimals..does anyone mind giving a helping hand??
Answer:
65 miles per gallon.
Step-by-step explanation:
Scale it down. [tex]78:1.2 = x:1.0[/tex] or, solving for x, [tex]x= \frac{78\cdot 1.0}{1.2} = 65[/tex] miles per gallon.
Russel wants to buy 3 identical gift cards. He wants to make sure his total cost is no more than $2 above or below $60. Which of the following inequalities represents this situation?
A|3c − 60| ≤ 2
B|60 + 3c| ≤ 2
C |3c − 2| ≤ 60
D |3c + 2| ≤ 60
Step-by-step explanation:
very imprecise phrasing.
I assume this means the cost should not be more than $2 above, and not less than $2 below $60.
the bottom line is : the difference between the price of the 3 gift cards and the planned budget of $60 must not be more than $2 (no matter what's the sign of the difference - hence the usage of absolute values).
the only answer calculating that difference and comparing it to the $2 threshold is A.
remember, a difference is always calculated by a "-" operation.
so, B and D disqualify.
C compares the price of the 3 cards with $2 and compares that result with the limit of $60.
yes, that protects against too expensive cards.
but no, it does NOT protect against to cheap cards. e.g. if the cards (3c) cost only $30, that inequality would still be true (but should not).
so, A is the correct answer.
Which product is modeled by the number line below
Answer:
the second option/b
Step-by-step explanation:
because -2*4 equals -8
Answer:The second option beacue -2*4 equal -8
Step-by-step explanation:
Help me please????!!!
Answer:
Helene invested $700 in the 5% interest account and $500 in the 10% interest account.
Step-by-step explanation:
Solve.
x−(−256)=−15
What is the solution to the equation?
Enter your answer as a simplified mixed number in the box.
x =
Step-by-step explanation:
[tex]x - ( - 256) = - 15 \\x + 256 = - 15 \\ x = - 15 - 256 \\ x = - 271[/tex]
Solve for the value of m
Answer:
m=37
Step-by-step explanation:
180-35=145
4m-3=145
4m=148
m=37
What is the product in simplest form −6/11⋅3/4
if 4 watches cost 76.800. Find the cost of 9 watches pls answer my question
Answer:
1 watch cost 19,200 (76800/4=19200)
9 watches cost 172,800 (9×19200=172800)
Step-by-step explanation:
Answer:
$172.8
Step-by-step explanation:
divide 76.800 by 4 to figure out how much each watch cost. Than once you got that answer multiply by 9 to find out the cost of 9 watches
76.800÷4= 19.2
19.2×9= 172.8
what is the rate of change of the function ?
Answer:
Rate Of Change Formula At its simplest, the rate of change of a function over an interval is just the quotient of the change in the output of a function (y) over the difference in the input of the function (x) (change in y/change in x)
Step-by-step explanation:
f(x)=5x-2 find the slope of f
Answer:
Slope = 5
Step-by-step explanation:
Standard slope intercept form: y = mx + b
where m = slope of the function
so m = 5
Hope this helps!
:) stay safe out there
Answer:
8
Step-by-step explanation: