Algebrahard · Past Paper
Solve for x: √(3x^2 + 6) = 9.
A5, -5
B25, -25
C±√5
D±√75
✓ Correct Answer: A — 5, -5
Square both sides: 3x^2 + 6 = 81 → 3x^2 = 75 → x^2 = 25 → x = ±5.
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