Algebra practice question

Answer: 2

Expand: 6x − 2 + 4 = 4x + 6, so 6x + 2 = 4x + 6. Subtract 4x: 2x + 2 = 6. Subtract 2: 2x = 4, x = 2. Check: 2(5) + 4 = 14 and 8 + 6 = 14.

Common wrong answers

If you answered 1

1 comes from 6x + 2 = 4x + 4 or a similar slip; the right side is 4x + 6.

If you answered 4

4 comes from 6x − 2 = 4x + 6 — the +4 outside the parentheses was dropped.

If you answered 0.5

0.5 comes from 6x + 2 = 4x + 3 — check the constants: 6 − 2 = 4, then 4 / 2 = 2.

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