Question

What is the axis of symmetry for the graph of y – 4x = 7 – x2 ?

Answer 1

y – 4x = 7 – x2

rewrite it:


y = -x^2+4x+7

complete the square:

y = -(x-2)^2 + 11

vertex: (2,11)

the axis of symmetry is the coordinate of x, i.e. x=2

Answer 2

axis of symmetry at x=2

Explanation:

`y - 4x = 7 - x^2`

LEts solve for y

Add 4x on both sides

`y=- x^2+4x+7`

To find axis of symmetry we use formula

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

the equation in the form of ax^2 + bx+c

a= -1 , b= 4

Plug in the values

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

So axis of symmetry at x=2