Algebra practice question

Answer: 7

Substitute y = 2x + 1 into the second equation: 3x + 2(2x + 1) = 16, so 3x + 4x + 2 = 16, 7x = 14, x = 2. Then y = 2(2) + 1 = 5. So x + y = 7. Check: 3(2) + 2(5) = 16.

Common wrong answers

If you answered 2

2 is just x. The question asks for x + y, so find y = 2(2) + 1 = 5 and add: 7.

If you answered 5

5 is just y. Add it to x = 2 to get the requested sum, 7.

If you answered 10

10 is x times y (2 × 5). The question asks for the sum, 2 + 5 = 7.

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