Solve the simultaneous equations 2x + 1y = 11 and 1x - 1y = 1. What is x + y?
Answer and explanation
Correct answer: C. 7
- Step 1: Eliminate one unknown by adding or subtracting suitable multiples of the equations.
- Step 2: The solution is x = 4, y = 3, so x + y = 7.
Answer
7.
Why not the others: 4: only x was given. 3: only y was given. 1: the values were subtracted instead of added.
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