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Question
If 49x – 57y = 172 and 57x – 49y = 252 then x + y = ?
Options
80
0
10
8
Solution
10
Explanation:
49x - 57y = 172
57x - 49y = 252
- + -
- 8x - 8y = - 80
∴ x + y = `(-80)/(-8) = 10`
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