87.8k views
4 votes
Solve the linear equation:


4^(2x+7) = 8^(2x-3)

User Leemes
by
6.1k points

1 Answer

5 votes

Answer:

x = 11.5

Explanation:

Taking the logarithm base 2 will transform this to a linear equation.

2(2x+7) = 3(2x -3)

0 = 3(2x -3) -2(2x +7) . . . . subtract the left side

0 = 2x -23 . . . . . . . . . . . . . simplify

0 = x - 23/2 . . . . . . . . . . . . divide by 2

11.5 = x . . . . . . . . . . . . . . . . add 11.5

The solution is x = 23/2 = 11.5.

_____

Check

This value of x makes the equation become ...

4^(2·23/2 +7) = 8^(2·23/2 -3)

4^30 = 8^20 . . . . . true

User Verhagen
by
6.8k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.