Answer:
x = -2 or 2
Explanation:
-x² + 10 = 6
Move everything to one side. I suggest moving the left side to the right so that the leading coefficient becomes positive.
0 = x² − 4
Factor the difference of squares:
0 = (x − 2) (x + 2)
Set each factor to 0 and solve.
x − 2 = 0
x = 2
x + 2 = 0
x = -2
Therefore, the solution is x = -2 or 2.