Bonsoir,
a) (x + 5)(x + 5) = 0
→ x + 5 = 0
x = 0 - 5
x = (-5)
b) (x - 7)(x - 7) = 0
→ x - 7 = 0
x = 0 + 7
x = 7b
c) (x - 1/2)(x - 1/2) = 0
→ x - 1/2 = 0
x = 0 + 1/2
x = 1/2
d) (2/5x - 3)(2/5x - 3) = 0
→ 2/5x - 3 = 0
2/5x = 0 + 3
2/5x = 3
2/5x = 15/5
2x = 15
x = 15 / 2
x = 7,5
