Question

If x -2y -6 = 0, find the value of x3–8y3–36xy –216.

Answer 1

Ans:- Given x - 2y - 6 = 0

To find:- x³ - 8y³ - 36xy - 216

Now,

x - 2y - 6 = 0

so, x - 2y = 6 --------- 1

, -2y - 6 = -x --------- 2

, -6 + x = 2y ---------- 3

Now,

=> (x - 2y - 6)³ = x³ - 8y³ - 216 + 3(x-2y)(-2y-6)(-6+x)

=> (0)³ = x³ - 8y³ - 216 + 3(6)(-x)(2y){from 1,2and3)

=> 0 = x³ - 8y³ - 216 - 36xy

hence the value of x³ - 8y³ - 216 - 36xy is zero

here is your answer

hope it will help you