Thomas W. answered 03/06/13
Effective Economics, Math, Finance, & Statistics Tutor
first simplify: 4x^2 - 15x + 19
Since this doesn't look to be easily factored, we should use the quadratic equation:
(-b +or- sqrt(b^2 - 2ac))/2a
a, b, c are the coefficients in front of each "chunk" of this equation.
a = 4, b = -15, c = 19 (now plug into formula)
(-(-15) +or- sqrt((-15)^2 - 4*4*19))/2*4 (simplify)
(15 +or- sqrt(225 - 304))/8
(15 +or- sqrt(-79)/8 (OOPS!!!!! there is a problem here. can't have a negative square root. either double check that the question is copied down properly, or we can continue to factor imaginary numbers.)
15/8 +or- 8.89(i)/8
*answer: 1.875 +or- 1.112(i)