Answer:
x = 0, 2
Step-by-step explanation:
[tex] {4}^{x} - 5( {2}^{x} ) + 4 = 0 \\ {({2}^{x})}^{2} - 5( {2}^{x} ) + 4 = 0 \\ {u}^{2} - 5u + 4 = 0 \\ (u - 1)(u - 4) = 0 \\ u = 1 \: or \: u = 4 \\ {2}^{x} = 1 \: or \: {2}^{x} = 4 = {2}^{2} \\ x = 0 \: or \: x = 2[/tex]