Question

solve for x: 4^x-2^(x+1)=15

Answer 1

\[4^{x}-2^{x+1}=15\]

Answer 2

\[
4^x=2^{2x}
\]

Answer 3

But then what do I do?

Answer 4

\[
2^{x+1}=2\cdot 2^x
\]

Answer 5

You can factor that out at least.

Answer 6

How?

Answer 7

Try \(u=2^x\) maybe

Answer 8

I am completely lost

Answer 9

\[
4^{x}-2^{x+1}=15
\]\[
(2^x)^2-2(2^x)=15
\]\(u=2^x,x=\log_2(u)\)\[
u^2-2u=5
\]

Answer 10

you don't know how to find the values of \(u\)?

Answer 11

No, this is like an intro to logs unit

Answer 12

do you know how to solve a quadratic equation? @iamnotasalad

Answer 13

Yes

Answer 14

Solve for \(u\) then....