SOLUTION: y=3x^2+18x-1 Determine the zeros of your function. Give an algebraic reason for the existence or nonexistence of real-valued zeros of your quadratic function.

Algebra ->  Functions -> SOLUTION: y=3x^2+18x-1 Determine the zeros of your function. Give an algebraic reason for the existence or nonexistence of real-valued zeros of your quadratic function.       Log On


   

Question 752728: y=3x^2+18x-1
Determine the zeros of your function. Give an algebraic reason for the
existence or nonexistence of real-valued zeros of your quadratic function.
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
3x%5E2%2B18x-1=0 and solving for x gives the zeros. Avoiding attempt at factoring, general solution to quadratic formula gives:

x=%28-18%2B-+sqrt%2818%5E2-4%2A3%2A%28-1%29%29%29%2F%282%2A3%29

x=%28-18%2B-+sqrt%28336%29%29%2F%282%2A3%29

x=%28-18%2B-+sqrt%283%2A2%2A7%2A2%2A2%2A2%29%29%2F%282%2A3%29

x=%28-18%2B-+4%2Asqrt%2821%29%29%2F%282%2A3%29=%28-3%2B-+%282%2F3%29sqrt%2821%29%29


x=-3-%282%2F3%29sqrt%2821%29 or x=-3%2B%282%2F3%29sqrt%2821%29