How to use the discriminant to find out what type of solutions the equation has for 3z^2 + z - 1 = 0?

1 Answer
George C.
May 31, 2015

3z^2+z-1 is of the form az^2+bz+c, with a=3, b=1 and c=-1.

The discriminant is given by the formula:

Delta = b^2-4ac = 1^2-(4xx3xx-1) = 1+12 = 13

Since Delta > 0, the quadratic has two distinct real roots. However, Delta is not a perfect square, so those roots are irrational (involving sqrt(13)).

Related questions
See all questions in Solutions Using the Discriminant
Impact of this question
1374 views around the world
You can reuse this answer
Creative Commons License