How i solve this optional chapter question of class 10th of exercise 3.7. This is also an important type of question so please guide me the best solution Solve the following pair of linear equations: (iv) (a – b)x + (a + b) y = a2 – 2ab – b2 (a + b)(x + y) = a2 + b2

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# Solve the following pair of linear equations: (iv) (a – b)x + (a + b) y = a2 – 2ab – b2 (a + b)(x + y) = a2 + b2 Q.7(4)

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(a + b) y + (a – b) x = a

^{2}− 2ab − b^{2}…………… (i)(x + y)(a + b) = a

^{2}+ b^{2}(a + b) y + (a + b) x = a

^{2}+ b^{2}………………… (ii)Subtracting equation (ii) from equation (i), we get

(a − b) x − (a + b) x = (a

^{2}− 2ab − b^{2}) − (a^{2}+ b^{2})x(a − b − a − b) = − 2ab − 2b

^{2}− 2bx = − 2b (b + a)

x = b + a

Substituting this value in equation (i), we get

(a + b)(a − b) +y (a + b) = a

^{2}− 2ab – b^{2}a

^{2}− b^{2}+ y(a + b) = a^{2}− 2ab – b^{2}(a + b) y = − 2ab

y = -2ab/(a+b)