AlgebraEasy–MediumSum of the coordinates of an intersection
Algebra practice question
In the xy-plane, the lines 2x − y = 7 and x + y = 5 intersect at the point (a, b). What is the value of a + b?
Answer: 5
Adding the equations gives 3x = 12, so x = 4 and y = 1. Then a + b = 5.
Common wrong answers
- If you answered 1
- 1 is b alone.
- If you answered 3
- 3 is a − b.
- If you answered 4
- 4 is a alone.
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