SOLUTION: Solve for x: 16^x-5(8^x)=0 Thanks :)

Question 387044: Solve for x: 16^x-5(8^x)=0
Thanks :)
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Solve for x: 16^x-5(8^x)=0
---
Convert to base 2:
2^(4x) = 5*2^(3x)
---
Divide both sides by 2^(3x) to get:
2^x = 5
---
Take the log:
x(log(2)) = log(5)
---
x = [log(5)]/[log(2)]
----
x = 2.3219
================
OR
2^(4x) - 5*2^(3x) =
Factor:
2^(3x)[2^x-5] = 0
----
2^(3x) = 0 or 2^x = 5
---
No power or 2 gives 0 so 2^(3x)=0 has no solution.
But 2^x = 5 has x = 2.3219 as a solution.
================
Cheers,
Stan H.
===============
RELATED QUESTIONS
Solve for x: x(5^x) +... (answered by edjones)

Topic. Solving exponential equation Solve for x giving 16^x-5*8^x=0 (Please help me (answered by Alan3354)

Solve for x... (answered by Fombitz)

Solve (25^x)-8*(5^x)=-16 (answered by basketball1127)

Solve: (x-5)(x+3)<=0... (answered by solver91311)

solve... (answered by Edwin McCravy)

Solve: 16^(x) + 4^(x+1) - 3 = 0... (answered by jim_thompson5910)

{{{16^x - 4^x - 2=0}}} solve for... (answered by MathTherapy)

Please help with the following: Use the quadratic formula to solve the quadratic... (answered by adamchapman)