Răspuns:
a)x²-25=0
ײ=+5,-5
x1=-5,x2=5
c)75(x+2)=24(2x-1)
75x+150=24(2×-1)
75x+150=48x-24
75x-48x+150=-24
75-48x=-24-150
27x=-24-150
27x=-174
d)225=(2x-1)×(2x-1)
225=(2x-1)²
(2x-1)²=225
2x-1=+15,-15
2x-1=-15
2x-1=15
x=7
2x-1=15
e)(x+3) × (x+3)=196
(x+3)²=196
x+3= +14,-14
f)(3x-1)×(3x-1)=256
(3x-1)²=256
3x-1=-16,+16
×=5
3×-1=16