Question

solve the following pair of linear equation by the method of cross multiplication (a+b) x+(a-b) y=a² + 2ab-b²;a=0​

Answer 1

Answer:

(a−b)x+(a+b)y=a

2

−2ab−b

2

----- (i)

(a+b)(x+y)=a

2

+b

2

-------- (ii)

Subtracting eq (i) by eq (ii), we get.

⇒(a−b)x−(a+b)x=a

2

−2ab−b

2

−a

2

−b

2

⇒−2bx=−2bx(a+b)

⇒x=(a+b)

∴(a+b)(a+b+y)=a

2

+b

2

⇒(a+b)

2

+(a+b)y=a

2

+b

2

⇒y=

a+b

−2ab

Ans.