Question

If 2x + 3y = 14 and xy = 2, find 8x^3 = 27y^3

Answer 1

Answer:

This Is Example

Step-by-step explanation:

Given,

2x−3y=10 and xy=16

2x−3y=10  

Cubing both the sides,

(2x−3y)  

3

=10  

3

 

⇒(2x)  

3

−(3y)  

3

−3(2x)(3y)(2x−3y)=1000 [Since (a−b)  

3

=a  

3

−b  

3

−3ab(a−b)]

⇒(2x)  

3

−(3y)  

3

−18xy(2x−3y)=1000 [Since xy=16 and 2x−3y=10]

⇒8x  

3

−27y  

3

−18×16×10=1000

⇒8x  

3

−27y  

3

−2880=1000

⇒8x  

3

−27y  

3

=1000+2880

⇒8x  

3

−27y  

3

=3880