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 = 2a2b2 ] ×1
b2x + ab y = a2b2 + ab3
b2x + a2y = 2a2b2
- - -
---------------------------------------------
0 + ay (b-a) = a2b2 + ab3 - 2a2b2
----------------------------------------------
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.
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 = 2a2b2 ] ×1
b2x + ab y = a2b2 + ab3
b2x + a2y = 2a2b2
- - -
---------------------------------------------
0 + ay (b-a) = a2b2 + ab3 - 2a2b2
----------------------------------------------
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.