Question

Find the value of x cube - 8y cube -36xy - 216 when x=2y + 6

Answer 1

i hope this will helpful 2 u

Answer 2

Answer:

Step-by-step explanation:

x³-8y³-36xy-216

given that x = 2y+6

(2y+6)³-8y³-36(2y+6)y-216

= 8y³+216+(3×2y×6)(2y+6)-8y³- 36y(2y+6)-216

= 8y³-8y³+216-216+36y(2y+6)-36(2y+6)

=0