Question

What is the solution of 7^3x = 400?

Answer 1

X= 400/343 simplify each side of the equation and isolate the variable 

Answer 2

Hi,
$7^{3x}=400\\\\ 3x*ln(7)=ln(400)\\\\ x= \dfrac{ln(400)}{3*ln(7)} \\\\ x =1,026334566... \\x\approx 1.03$