-x2 = x - 6 x2 + x - 6 = 0 (x - 2)(x + 3) = 0 x ∈ {-3, 2}
-4
3
x2 - x - 6 = (x - 3)(x + 2) = 0; whence, x = 3 or -2.
x2-2x-3 = 0 (x+1)(x-3) = 0 x = -1 or x = 3
If: x2 = 3 Then: x = square root of 3
x2 + 2x - 15 = (x - 3)(x + 5)
2x = x2 + 4x - 3 x2 + 2x - 3 = 0 (x - 1)(x - 2) = 0
x2+3=124 x2=121 x= square root(121) x=11
x2 + 4x - 9 = 5x + 3 ∴ x2 - x - 12 = 0 ∴ (x + 3)(x - 4) = 0 ∴ x ∈ {-3, 4}
-7
x2 + 6x + 12 = 0 x2 + 6x + 9 = -3 (x + 3)2 = -3 x + 3 = ± √-3 x = -3 ± i√3