1.
If no changes are made, the school has a revenue of :
625*400$/student=250,000$
2.
Assume that the school decides to reduce n*20$.
This means that there will be an increase of 50n students.
Thus there are 625 + 50n students, each paying 400-20n dollars.
The revenue is:
(625 + 50n)*(400-20n)=12.5(50+n)*20(20-n)=250(n+50)(20-n)
3.
check the options that we have,
a fee of $380 means that n=1, thus
250(n+50)(20-n)=250(1+50)(20-1)=242,250 ($)
a fee of $320 means that n=4, thus
250(n+50)(20-n)=250(4+50)(20-4)=216,000 ($)
the other options cannot be considered since neither 400-275, nor 400-325 are multiples of 20.
Conclusion, neither of the possible choices should be applied, since they will reduce the revenue.
Answer:
1={5 and 3} 2={0} 3={0.209 and 4.791} 4={-3 and 4} 5={1 and 9} 6={-4.303 and -0.697}
Step-by-step explanation:
Your probably confused on what a, b, and c means.
The problems are written like this.

That formula finds the zeros.
For example 1:

Then use the formula

If plus then 5, if minus then 3
CHECK:

Hope this helps you understand how to do this by yourself. Now to do the rest ;-;
Part (A)
We have n = 5 sides, so the measure of any exterior angle of a regular pentagon is E = 360/n = 360/5 = 72
Each interior angle is therefore 180-E = 180-72 = 108 degrees.
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Alternatively, you could use the formula below with n = 5
i = interior angle
i = 180(n-2)/n
i = 180(5-2)/5
i = 180(3)/5
i = 540/5
i = 108
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<h3>Answer: 108 degrees</h3>
====================================================
Part (B)
We're told that CDF is 70 degrees. From part (A) we know that angle CDE is 108 degrees, so this must mean that angle EDF is 108-70 = 38 degrees.
Similarly, angle FEA is 85 degrees, which subtracts from angle AED to get 108 - 85 = 23 degrees. This is the measure of angle DEF.
So far we found
angle EDF = 38
angle DEF = 23
Let's call these x and y for shorthand. Let z be the missing third angle of triangle DFE.
So,
x+y+z = 180
38+23+z = 180
61+z = 180
x = 180-61
x = 119
Interior angle DFE is 119 degrees.
Note how 90 < x < 180 showing we have an obtuse angle. It is not a reflex angle because the statement 180 < x < 360 is false.
So we subtract the value of x from 360
360-x = 360-119 = 241
This is the reflex angle DFE
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<h3>Answer: 241 degrees</h3>
Answer: 17
Step-by-step explanation: Trust me, G!