This graph represents a quadratic function

What is the value of a in this function's equation ?
A.
1
B.
-2
C.
-1
D.
2

step-by-step explanation:

the ratio of red paint to blue paint is always 9/7. that means that, whatever x's value, (4x+12)/(4x-4) has that same ratio. so, set up an equation and cross-multiply to solve for x:

9/7 = (4x+12)/(4x-4)

9(4x-4) = 7(4x+12)

36x - 36 = 28x + 84

8x - 36 = 84

8x = 120

x = 15

twenty-six miles over two gallons because the proportion for the original 13 miles to one gallon would be written 13/1 and, doing the same thing to the top and bottom, i multiplied by 2 and got 26/2

answer: c. im 100 percent sure

step-by-step explanation:

i think this is a open ended question but i agree with other guy who said you should ask it at english section