Algebra practice question

Answer: 5

The equations must be proportional: 9/6 = 3/2, so a/2 = 3/2 gives a = 3, and 3/b = 3/2 gives b = 2. Then a + b = 5.

Common wrong answers

If you answered 1

1 comes from b = −2 with the wrong sign.

If you answered 6

6 uses a = 3 and b = 3, matching coefficients instead of ratios.

If you answered 4.5

4.5 sets both a and b to the ratio 1.5 and adds, but a and b are not themselves the ratio.

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