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a(x+y)+b (x-y)=a^2-ab+b^2;a(x+y)-b(x-y)=a^2+ab+b^2 |
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Answer» Given: a(x+y) + b(x-y) = a² - ab + b² ..(i)., a(x+y) - b(x-y) = a² + ab - b² ...(ii) _____________________________________________________________ To find, The values of x and y. _____________________________________________________________ Adding both the equations, We get, => a(x + y) + b(x - y) + a(x + y) - b(x - y) = a² - ab + b² + a² +ab - b² => 2a(x + y) = 2a² => x + y = a ...(iii),____________________ Subtracting (ii) from (i), => a(x + y) + b(x - y) -(a(x + y) - b(x - y)) = a² - ab + b² - (a² + ab -b²) => a(x + y) + b(x - y) - a(x - y) + b(x - y) = a² - ab + b² - a² - ab + b² => 2b(x - y) = -2ab + 2b² => 2b(x - y) = 2b² - 2ab => 2b(x - y) = 2b(b - a) => x - y = b - a ..(iv) _______________________ Adding (iii) & (iv), We get, => (x + y) + (x - y) a + b- a => 2x = b=> x = b/2 substitute value of x in (iv)y= a - b/2 |
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