2 this Domo
x2 + 8x - 6 = 0 x2 + 8x + 16 = 22 (x + 4)2 = 22 x + 4 = ± √22 x = -4 ± √22
x2+8x+9 = -7 x2+8x+9+7 = 0 x2+8x+16 = 0 (x+4)(x+4) = 0 Therefore: x = -4 and also x = -4 (they both have equal roots)
x + 4
x2 - 8x = 1 ∴ x2 - 8x + 16 = 17 ∴ (x - 4)2 = 17 ∴ x - 4 = ±√17 ∴ x = 4 ± √17
X2 + 8x + 16 = 10x +16x2 + 8x + 16=2x + 8x + 16=10x + 16
2 this Domo
x2 + 8x - 6 = 0 x2 + 8x + 16 = 22 (x + 4)2 = 22 x + 4 = ± √22 x = -4 ± √22
(x + 4)(x +4) or (x + 4)squared
x2+8x+9 = -7 x2+8x+9+7 = 0 x2+8x+16 = 0 (x+4)(x+4) = 0 Therefore: x = -4 and also x = -4 (they both have equal roots)
x2 + 8x - 5 = 0 ∴ x2 + 8x + 16 = 21 ∴ (x + 4)2 = 21 ∴ x + 4 = ± √21 ∴ x = -4 ± √21
no
In general, no.
x + 4
x2 + 8x - 2 = 0 => x2 + 8x = 2 => x2 + 8x + 16 = 2 + 16 = 18 => (x + 4)2 = 18 => x + 4 = +or- sqrt(18) = +or- 3*sqrt(2) so x = -4 +or- 3*sqrt(2)
x - x2 - 9x + 14 = 0 ; whence, x2 + 8x = 14 , x2 + 8x + 16 = 30 , and x + 4 = ±√30 . Therefore, x = ±√30 - 4 .
x2 - 8x = 1 ∴ x2 - 8x + 16 = 17 ∴ (x - 4)2 = 17 ∴ x - 4 = ±√17 ∴ x = 4 ± √17