# How to use the discriminant to find out how many real number roots an equation has for #a^2 + 12a + 36 = 0#?

##### 2 Answers

May 20, 2018

The discriminant is:

Substitute these values into the discriminant and you should get two answers (real roots):

If the discriminant is 0 there is 1 real root, if it is > 0 there are 2 and otherwise 0 real roots.

May 20, 2018

one at

#### Explanation:

discriminant is the part under the square root:

if discriminant < 0 there are 2 imaginary roots

if discriminant > 0 there are 2 real roots

if discriminant = 0 there is 1 real root

if discriminant is a perfect square roots are rational

for yours:

a = 1

b = 12

c = 36

since the discriminant is 0 the function has 1 real root at

graph{x^2+12x+36 [-13.79, 6.21, -0.92, 9.08]}