(2-х)^2-x(x+3)=18 решите уравнение

2^x + 2^(x-3) = 18 2^x (1+2^(-3)) = 18 2^x (1+1/8) = 18 2^x * 9/8 = 18 2^x = 18*8/9 2^x = 16 2^x = 2^4 x = 4

4-4х+х^2-х^2-3х=18 -7х=18-4 -7х=14 х=-2