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Solve x/a + y/b = a + b, x/a2 + y/b2 = 2

Problem : Solve x/a + y/b = a + b, x/a2 + y/b2 = 2

Doubt by Ananya

Solution :

 x/a + y/b = a + b
(bx+ay)/ab = a+b
bx + ay = ab(a+b) ---- (1)


x/a2 + y/b2 = 2
(b2x + a2y)/a2b2 = 2
b2x + a2y = 2a2b2---- (2)

Solving these equations by elimination method

[ bx + ay = ab(a+b) ] × b
[ b2x + a2y = 2a2b] ×1

b2x + ab y = a2b2 + ab3
b2x + a2y = 2a2b2
-      -          -
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0 + ay (b-a) = a2b2 + ab3 - 2a2b2
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ay (b-a) = ab2 - a2b2
ay (b-a) = ab2 (b-a)
ay = ab2
y = b2

putting this value of y in equation (1)

bx + a(b2) = ab(a+b)
bx = a2b + ab2 -ab2
bx = a2b
x = a2 

Pro Tip - Try to solve these questions by cross multiplication method.