5²× - 30 · 5× + 125 =0

Question

5²× - 30 · 5× + 125 =0

Answer 1

Пусть 5×=t тогда t>0
t^2-30t+125=0

D=900-4×125=900-500=400=20
t1=-30+20/2=10/2=5
t2=-30-20/2=50/2=25

5×=5
x=1
5×=25
x=2