Question

PLEASE HELP ME I DONT KNOW THE ANSWERR

Answer 1

Let u = x^(1/3)

Then,

u^2 - 6u - 27 = 0

(u-9)(u+3)=0
u = 9, u = -3

Substitute back

X^(1/3) = 9
(X^(1/3))^3 = 9^3
X = 729

And
X^(1/3) = -3
(X^(1/3))^3 = -3^3
X = -27

Answer 2

I can’t see the question bro