Given the following equation of a quadratic function:
[tex]h(x)=2x^2+8x−4[/tex]We will rewrite the quadratic function in standard form.
The general standard form will be as follows:
[tex]h(x)=a(x+h)^2+k[/tex]So, we will make a complete square for the given function as follows:
[tex]\begin{gathered} h(x)=2x^2+8x−4 \\ h(x)=2(x^2+4x)-4 \\ h(x)=2(x^2+4x+4-4)-4 \\ h(x)=2(x^2+4x+4)-2*4-4 \\ \\ h\mleft(x\mright)=2\left(x+2\right)^2-12 \end{gathered}[/tex]Comparing the last result to the general form:
h = -2, k = -12
So, the answer will be:
[tex]h(x)=2(x+2)^{2}-12[/tex]The vertex = (x,y) = (-2, -12)