Question

a)X^2-81=0
B)X^2-121=0
C)3X^2-5X=0
D)X^2-X=0
E)9X^2-16=0

Answer 1

Resposta:

$a) {x}^{2} - 81 = 0 \\ ( x - 9)(x + 9) = 0 \\ x = 9 \\ x = - 9$

$b) {x}^{2} - 121 = 0 \\ (x - 11)(x + 11) = 0 \\ x = 11 \\ x = - 11$

$c) {3x}^{2} - 5x = 0 \\ x(3x - 5) = 0 \\ x = 0 \\ x = \frac{5}{3}$

$d) {x}^{2} - x = 0 \\ x(x - 1) = 0 \\ x = 0 \\ x = 1$

$e) {9x}^{2} - 16 = 0 \\ (3x - 4)(3x + 4) = 0 \\ x = \frac{4}{3} \\ x = - \frac{4}{3}$