Question
If 2x + y = 10 and 3x - 2y = 5, find the value of x +
y.Solution
From the first equation, y = 10 - 2x. Substitute y = 10 - 2x into the second equation: 3x - 2(10 - 2x) = 5. 3x - 20 + 4x = 5. 7x = 25. x = 25/7. Substitute x = 25/7 into y = 10 - 2x: y = 10 - 2(25/7). y = 10 - 50/7. y = 70/7 - 50/7. y = 20/7. x + y = 25/7 + 20/7 = 45/7. Correct option: a
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