How do you solve 5^x + 4(5^(x+1)) = 63?

1 Answer
Dec 16, 2015

x=log_5(3)

Explanation:

Given:
color(white)("XXX")5^x+4(5^(x+1))=63

Extract the common factor of 5^x from both terms on the left side:
color(white)("XXX")5^x(1+4(5^1))=63
Simplify the numeric expression
color(white)("XXX")5^x(21)=63
Divide both sides by 21
color(white)("XXX")5^x=3
Apply the equivalence: log_b a =c hArr b^c=a
color(white)("XXX")x=log_5(3)