Question

Solve for x: 81^3-x=(1/3)^5x-1

Answer 1

use index laws


Left hand side


\[81^{3 - x} = (3^3)^{3 - x} = 3^{9 - 3x}\]

Right hand side

\[(1/3)^{5x -1 } = (3^{-1})^{5x - 1} = 3^{-5x + 1}\]

now both sides are to the same base equate the powers

9 - 3x = -5x + 1

2x = -8

x = -4

Answer 2

thanks!