Question

Tìm x 
2^2x + 4^{x + 2} = 272 

Answer 1

\(2^{2x}+4^{x+2}=272\)
\(\Rightarrow4^x+4^x\cdot4^2=272\)
\(\Rightarrow4^x\left(1+4^2\right)=272\)
\(\Rightarrow4^x\cdot17=272\)
\(\Rightarrow4^x=16\)
\(4^x=4^2\)
\(\Rightarrow x=2\)