Benjamin's credit card has an APR of 19%, calculated on the previous monthly
balance, and a minimum payment of 2%, starting the month after the first
purchase. His credit card record for the last 7 months is shown in the table
below.
End of Previous New
Payment Finance Principal New
month balance charges received charges paid balance
$0.00 $2400.00 $0.00 $0.00 50.00 $2400.00
$2400,00
$38.00 $10.00 $2390.00
$2390 00
$2380 04
$2380.04
59 92 $2370. 12
$2370.12
$2360 25
$2360.25
$2350.41
$2350.41
$2340.62
NOUAWN
$9.96
$9 88
$9.83
$9.79
What is the total amount that Benjamin has made in payments over the 7
months?

let's cover over the formula of the vertex:

y = a(x – h)^2 + k

in this formula, (h,k) are the vertex, always remember that the positive or negative value of the vertex is based on the sign it has.

for example, if the vertex is -3,-6 then both the x and y value would have the positive sign attached to it and if it were a positive x and y value, then a negative sign would be attached to it.

with that being said, for our problem the x value is a positive one so we are looking for a number with a negative sign next to it, in this case the first and second choice.

however, for the first answer choice it isn't quite part of the formula so we know that the answer choice correctly displays the x value.

to confirm, we can see if the -1 fits correctly with the second answer choice, and as mentioned above a negative number will have a positive sign attached to it. so, for our problem we can see that -1 has been changed to +1, so we can confirm that the second answer choice is correct.

hence, our final answer is y=(x - 1)^2 + 1

the formula of a slope:

we have the points (-2, 7) and (2, 3). substitute: