Question

Find the co-ordinates of the vertex of the function y=x²-12x+2 and show your work

Answer 1

vertex = (6, - 34 )

the equation of a parabola in vertex form is

y = a(x - h)² + k

where (h, k ) are the coordinates of the vertex and a is a multiplier

To obtain this form, complete the square on x² - 12x

• add/subtract (half the coefficient of the x- term )²

y = x² + 2(- 6 )x + 36 - 36 + 2 = (x- 6 )² - 34 ← in vertex form

vertex = (6, - 34 )

Answer 2

(6,-34)

Explanation:

You can use the vertex formula to find the x of the vertex and then plugin the x value into the formula to find the y value.

`x = -(b)/(2a)`

`x = -(b)/(2a)`

`x = -(-12)/(2(1))`

`x = 6}`

Now plugin 6 into y=x²-12x+2

y=x²-12x+2

y=6²-12(6)+2

y=36-72+2

y=36-72+2

y = -34

Vertex = (6,-34)