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Question
If 3x + 2y = 10 and 2x + 3y = 15, then find the value of x + y.
Solution
3x + 2y = 10 ..........(i)
2x + 3y = 15 ........(ii)
Adding equation (i) and (ii)
3x + 2y = 10
2x + 3y = 15
_________________
5x + 5y = 25
∴ 5 (x + y) = 25
∴ x + y = `25/5`
∴ x + y = 5
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