Answer:
2 or -2
Step-by-step explanation:
If x² - 8x = -12
Step 1
We find x by solving
x² - 8x = -12
We equate to zero
x² - 8x + 12 = 0
We factorise
x² - 6x - 2x + 12 = 0
x(x - 6) -2(x - 6) = 0
(x - 6) (x - 2) = 0
x - 6 = 0, x = 6
x - 2 = 0, x = 2
x = 6 or 2
Step 2
What is x - 4?
When x = 6
= 6 - 4 = 2
When x = 2
= 2 - 4 = -2
Therefore, x - 4 = 2 or -2
