We are given the following quadratic equation
[tex]y=2x^2-32x+56[/tex]
We are asked to convert this equation into the vertex form given by
[tex]y=a(x-h)^2+k_{}[/tex]
Let us convert the given quadratic equation into the above form.
[tex]\begin{gathered} y=2x^2-32x+56 \\ y-56=2x^2-32x \\ y-56=2(x^2-16x) \end{gathered}[/tex]
Now we have to add a number to both sides of the equation such that the terms inside the parenthesis become perfect squares.
How about 64?
[tex]y-56+128=2(x^2-16x+64)[/tex]
Why did we add 128 on the left side?
Because 64 is being multiplied by 2 on the right side of the equation so 64x2 = 128
[tex]\begin{gathered} y-56+128=2(x^2-16x+64) \\ y+72=2(x-8)^2 \\ y=2(x-8)^2-72 \end{gathered}[/tex]
As you can see, the equation has been converted into the vertex form.
Finally, the x-coordinate of the minimum is
The value of h is the x-coordinate of the minimum and the value of k is the y-coordinate of the minimum
Comparing the above equation with the standard vertex form, we see that
h = 8
Therefore, 8 is x-coordinate of the minimum