Question

I need help, urgently.

Answer 1

Answer:

y = -0.5(x - 4)^2 + 5.

y = -0.5x^2 + 4x - 3.

Step-by-step explanation:

The vertex is at (4, 5).  so we have:

f(x) = a(x - 4)^2 + 5

When x = 0 y = -3 so substituting in the above:

- 3 = a(0-4)^2 + 5

-8 = 16a

a = -0.5.

So the vertex form is y = -0.5(x - 4)^2 + 5.

Standard form:

y = -0.5(x^2 - 8x + 16) + 5

y = -0.5x^2 + 4x - 8 + 5

y = -0.5x^2 + 4x - 3.