Question

The vertex form of the equation of a parabola is x = (y - 2)2 + 36. 

What is the standard form of the equation?  
A.

x = 2y2 - 4y + 40  
B. x = y2 + y + 12  
C. x = y2 - 4y + 40
D. x = y2 + 4y + 36

Answer 1

Ok to do this we need to multiply out the brackets:
x=y²-4y+40 therefore C is the answer.

Answer 2

Option C is correct

`x = y^2-4y+40`

Explanation:

The standard for of the quadratic equation is given as:

`x= Ay^2+By+C`

As per the statement:

The vertex form of the equation of a parabola is:

`x = (y-2)^2+36`

Using identity rule:

`(a-b)^2 = a^2-2ab+b^2`

then;

`x = y^2-4y+4+36`

⇒
`x = y^2-4y+40`

Therefore, the standard form of the equation is,
`x = y^2-4y+40`