How do you find the value of the discriminant and determine the nature of the roots #r^2+5r+2=0#?

Question

1475 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2017-04-13T13:21:46

#Delta=17#

#" roots are real and unequal"#

For any quadratic #" "ax^2+bx+c=0#

the discriminant is given by#" "Delta=b^2-4ac#

the nature of the roots is determined by the following;

#Delta>0=>"roots are real and unequal"#

#Delta=0=>"roots are real and equal"#

#Delta<0=>"roots are imaginary"#

for #" "r^2+5r+2=0#

#a=1, b=5, c=2#

#Delta=5^2-4xx1xx2#

#Delta=25-8=17>0#

#:." roots are real and unequal"#