a) x = V1 = ±1
x² = 81
x = V81 = ± 9
x² = 1/4
x = V1/4 = ± 1/2
b) x² = 75/3
x² = 25
x =V25 = ±5
x² = 121/49
x = V121/49 = ±11/7
x² = 225/25
x = V225/25 = ±15/5 = ±3
c) x² = 0,25
x = V25/100 = ± 5/10 = ± 1/2
2x² = 32/100
x² = 32/100 * 1/2
x = V16/100 = ± 4/10 = ± 2/5
x² = 4/100 * 1/4
x = V1/100 = ±1/10
