Advanced Math practice question

Answer: 3

2n² − n − 15 = (2n + 5)(n − 3) = 0, so n = 3 (the other root, −5/2, is negative).

Common wrong answers

If you answered 2

2 gives 8 − 2 = 6.

If you answered 5

5 gives 50 − 5 = 45.

If you answered -2.5

−2.5 is the negative root.

More Advanced Math questions

• Easy–Medium
  If f(x) = 2x² − 3, what is f(4)?
• Easy–Medium
  Which expression is equivalent to (2x³)(3x⁴)?
• Easy–Medium
  What are the solutions to x² − 16 = 0?
• Easy–Medium
  Which expression is equivalent to (x + 5)²?
• Easy–Medium
  For x ≠ 0, which expression is equivalent to (x² + 3x) / x?
• Easy–Medium
  What are the solutions to the equation 2(x − 3)² − 32 = 0 ?