Answer:
Step-by-step explanation:
Rewrite this quadratic in standard form by subtracting 39 from both sides. We get:
5x^2 - 10x - 60 = 0
Reduce this by dividing all four terms by 5:
x^2 - 2x - 12 = 0
Use the quadratic equation to find the roots. The coefficients of the x terms are 1, -2, -12. Thus the discriminant is b^2 - 4ac, or:
(-2)^2 - 4(1)(-12) = -44 of which 4 is a perfect square factor and 11 is not.
Because the discriminant is negative, the given equation has two unequal, complex roots, which are:
-(-10) ± i√4√11
x = -----------------------
10
or x = 1 ± (1/5)√11
