`7) 2^{x + 3} - 3 * 2^{x + 1} = 32`
`2^{x + 1} * 2^2 - 3 * 2^{x + 1} = 32`
`2^{x + 1} * (4 - 3) = 32`
`2^{x + 1} * 1 = 2^5`
`2^{x + 1} = 2^5`
`x + 1 = 5`
`x = 4`
Vậy `x = 4`
`8) 221 - (3x + 2)^3 = 96`
`(3x + 2)^3 = 221 - 96`
`(3x + 2)^3 = 125`
`(3x + 2)^3 = 5^3`
`3x + 2 = 5`
`3x = 3`
`x = 1`
Vậy `x = 1`