Question

Value of x such that 4^(x+1) = 2 - 7(2^x) is:​

Answer 1

4^x(4) = 2 - 7(2^x)
Let 2^x = y
4 y^2 = 2 -7y
4 y^2+7y-2=0
4 y^2+8y-y-2=0
(4y-1)(y+2)=0
y = 1/4 or y = -2(rejected)
2^x = 2^(-2)
Therefore, x = -2