Question

The standard form of the equation of a parabola is x = y2 - 4y + 20.

Answer 1

Answer:

The correct option is B.

Step-by-step explanation:

The given equation is

$x=y^2-4y+20$

It can be written as

$x=(y^2-4y)+20$

Add and subtract $(-\frac{b}{2a})^2$ in the parenthesis.

$(-\frac{b}{2a})^2=(\frac{-4}{2(1)})^2=(-2)^2=4$

Add and subtract 4 in the parentheses.

$x=(y^2-4y+4-4)+20$

$x=(y^2-4y+4)-4+20$

$x=(y+2)^2+16$

Therefore option B is correct.

Answer 2

If you would like to find the vertex form of the equation, you can calculate this using the following steps:

x = y^2 - 4 * y + 20
x = (y - 2)^2 - 4 + 20
x = (y - 2)^2 + 16

The correct result would be B. x = (y - 2)^2 + 16.