What is the equation of the quadratic function represented by this graph

Step-by-step explanation:

f(0) = 8       {y-axis intercept = (0, 8)}

Vertex = (1, 9)

f(x) = a(x - 1)² + 9

8 = a(0-1)² + 9

8 = a + 9

a = -1

f(x) = - (x - 1)² + 9

f(x) = - (x² - 2x + 1) + 9

f(x) = - x² + 2x - 1 + 9

f(x) = - x² + 2x + 8

x₁ = -2  and x₂ = 4, so also:

f(x) = -(x + 2)(x - 4)

step-by-step explanation: h: (- 3, 6)

m: (1, - 2)

o: (7, 6)

r: (- 9, - 2)

midpoint of hm: (- 1, 2)

midpoint of or: (- 1, 2)

therefore, b is the midpoint of both diagonals bisect each other !

to prove the diagonals are perpendicular, show that the product of the slopes = - 1

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