if x=2y+6,then find the value of x3-8y3-36xy-216

 

Given:- x=2y+6

x-2y-6=0 ----------------- (1)

x3- 8y3- 216 - 36xy

= (x)3+ (-2y)3+ (-6)3-3*x*(-2y)*(-6)

=(x-2y-6) (x2+4y2+36+2xy-12y+6x)

=0 (x2+4y2+36+2xy-12y+6x)  (from equation (1) )

=0

  • 57

x = 2y + 6

3x - 8y3 - 36xy - 216

3(2y + 6) - 8 x 3y - 36 (2y + 6) - 216

6y + 18 - 24y - 72y - 216 - 216

6y - 24y - 72y - 432

-18y - 72y - 432

-54y - 432  That's Solve 

  • -14

its x3 and not 3x

  • -11

2y3+18 x 8y3+6y x 36+216-8y3-72y2-216y-216

144y3-72y2

  • -9
What are you looking for?