How do you find the discriminant #2x^2+3x-9=0#?

1 Answer
Feb 14, 2017

Answer:

Discriminant is #81#

Explanation:

#2x^2+3x-9=0#
Comparing with general quadratic equation #ax^2+bx+c=0 # we get #a=2 ,b= 3 , c= -9#
Disciminant is #D=b^2-4ac or D= 3^2 -4 * 2* (-9) = 9 +72 = 81#

If #D >0 # , there is 2 real solution.
If #D =0 # , there is 1 real solution.
If #D<0 # , there is no real solution , roots are imaginary.
Discriminant is #81# [Ans]