SOLUTION: use the discriminant to determine the number of solutions of the quadratic equation, and whether the solutions are real or complex. Note: It is not necessary to find the roots; jus

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: use the discriminant to determine the number of solutions of the quadratic equation, and whether the solutions are real or complex. Note: It is not necessary to find the roots; jus      Log On


   

Question 36095: use the discriminant to determine the number of solutions of the quadratic equation, and whether the solutions are real or complex. Note: It is not necessary to find the roots; just determine the number and types of solutions.
2x^2 + x - 1 = 0
Answer by venugopalramana(3286) About Me  (Show Source):
You can put this solution on YOUR website!
use the discriminant to determine the number of solutions of the quadratic equation, and whether the solutions are real or complex. Note: It is not necessary to find the roots; just determine the number and types of solutions.
2x^2 + x - 1 = 0...EQN. IS AX^2+BX+C=0...A=2..B=1...C=-1
DISCRIMINANT = B^2-4AC.....
1^2-4*2*(-1)=1+8=9=POSITIVE AND PERFECT SQUARE
HENCE ROOTS ARE REAL AND DISTINCT AND RATIONAL