Please answer this question?

Assuming a quadratic, we have that

y = ax^2 + bx + c

Since (0,5) is on the graph, c =5

And we have the remaining system

a(9)^2 + b(9) + 5 = -11

a(6)^2 + b(6) + 5 = 13 simplify

81a + 9b = -16 multiply through by 6 ⇒ 486a + 54b = - 96 (1)

36a + 6b = 8 multiply through by -9 ⇒ -324a -54b = -72 (2)

Add (1) and (2)

162a = -168

a = -28/27

To find b we have

36 (-28/27) + 6b = 8

-112/3 + 6b = 8

⇒ b = 68/9

The function is

y = - (28/27)x^2 + (68/9)x + 5

Step-by-step explanation:

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