4^x+3*2^x=28 плиззз,,,,,

Question

4^x+3*2^x=28 плиззз,,,,,

Answer 1

Замена: x^2=t
t^2+3t-28=0
D=9+112=121
t1=(-3+11)/2=4
t2=(-3-11)/2=-7
x^2≠-7
x^2=4
x=±2