Question

Find a formula for a quadratic function with vertex at (-2,8) and y intercept (0,7)

Answer 1

Givens.

• The vertex is (-2,8).

,

• The y-intecept is (0,7).

Given that we know the vertex and the y-intercept, we can use the standard form to find the equation.

`f(x)=a(x-h)^2+k`

Where h = -2, k = 8, x = 0, and f(x) = 7. Find a.

`\begin{gathered} 7=a(0-(-2))^2+8 \\ 7=a(4)+8 \\ 7-8=4a \\ a=(-1)/(4) \end{gathered}`

Once we have a, we can write the complete formula for the function.

`f(x)-(1)/(4)(x+2)^2+8`