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

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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 $" "r^2+5r+2=0$

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

$Delta=5^2-4xx1xx2$

$Delta=25-8=17>0$

$:." roots are real and unequal"$

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