Question

Determine a solução de:
5^x + 5^x+1 + 5^x-1 = 31

Answer 1

5^x = u

u + 5u +u/5 = 31

5u +25u +u = 31 * 5

u = 31 * 5/31

u = 5

5^x = 5^1

x = 1