Advanced Math practice question

Answer: 4

Substitute y = 3x: x² + 9x² = 40 → 10x² = 40 → x² = 4.

Common wrong answers

If you answered 2

2 is x (one of the values), but the question asks for x².

If you answered 10

10 comes from x² + 3x² = 40, squaring only x but not the 3.

If you answered 36

36 is y² when x² = 4.

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