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Question
Solve by the method of elimination
x – y = 5, 3x + 2y = 25
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Solution
x – y = 5 → (1)
3x + 2y = 25 → (2)
(1) × 2 ⇒ 2x – 2y = 10 → (3)
(2) × 1 ⇒ 3x + 2y = 25 → (2)
(3) + (2) ⇒ 5x + 0 = 35
x = `35/5`
= 7
Substitute the value of x = 7 in (1)
x – y = 5
7 – y = 5
– y = 5 – 7
– y = – 2
y = 2
∴ The value of x = 7 and y = 2
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The monthly income of A and B are in the ratio 3 : 4 and their monthly expenditures are in the ratio 5 : 7. If each saves ₹ 5,000 per month, find the monthly income of each
