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Question
If 3x + 5y = 9 and 5x + 3y = 7 find the value of x + y.
Solution
3x + 5y = 9 ........(1)
5x + 3y = 7 ........(2)
8x + 8y = 16 .............Adding (1) and (2)
x + y = 2 ............. dividing by 8
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