Question

Write down the turning point of the graph y=x^2 - 8x + 22

Answer 1

y=6

Explanation:

Differentiate the equation

dy/dx=2x-8

Find the value of x in equation form

2x-8=0

x=8/2=4

Now x=4 is the line of symmetry or the parabola of the quadratic equation.

Plug back x=4 into the equation to find the turning point(minimum value)

y=(4)²-8(4)+22

y=16-32+22

y=6

Answer 2

(4 , 6) is the vertex. I guess that can be called the "turning point"

Explanation:

Use vertex formula : x =
`(-b)/(2a)`

x =
`(-(-8))/((2)(1))` =
`(8)/(2)` = 4

Substitute x in original equation and solve for y:

y =
`4^(2)` - 8(4) + 22

y = 16 - 32 + 22

y = 6