Explanation:
A
let's bring everything on the right hand side back under the square root :
8² = 64
(x³)² = x⁶
so, we get
sqrt(448x^c) = sqrt(64×7×x⁶×x) = sqrt(448×x⁷)
therefore, c = 7
B
similar to A let's bring everything on the right side under the cubic root :
4³ = 64
(x)³ = x³
cubic root(576x^d) = cubic root(64×9×x³×x²) =
= cubic root(576×x⁵)
therefore, d = 5