Answer:
Step-by-step explanation:
Take out a common factor of -1 from the first 2 terms
y = -(x^2 - 6x ) - 4
Take -6 and multiply it by 1/2 and square the result. Add inside the brackets
y = -(x^2 -6x +(-3)^2 ) - 4
y = -(x^2 - 6x + 9) - 4
Because you added nine inside the brackets add 9 outside the brackets
y = -(x^2 - 6x + 9) - 4 + 9
The reason you add 9 outside the brackets is because of the minus sign on the left of the brackets. Without that minus sign, you would subtract 9.
Result
y = -(x^2 - 6x + 9) + 5
Now what is inside the brackets is a perfect square
y= -(x -3)^2 + 5
The axis of symmetry is x = 3 (see the graph below)
4
