2022 · Q24
If log₁₀[995+√(x²-12x+60)]=3, then what is the sum of the roots of the equation?
Elementary MathematicsAlgebra
- A12
- B11
- C10
- D9
Explanation
log₁₀[…] = 3 gives 995 + √(x²−12x+60) = 1000, so x²−12x+60 = 25, i.e. x²−12x+35 = 0. The sum of its roots is 12. The keyed option is A.