Discriminant

This week in math we learned about discriminants.

The discriminant is .  The discriminant comes from part of the quadratic formula.  We use the discriminant to determine how many solutions and real roots a quadratic equation has.

Now that we know what the discriminant formula we need to know what the variables stand for.  If I had a quadratic equation of…

A = 3, B = 4, C = 2.

Now we take the discriminant and then replace each variable with the corresponding number…

Then we solve…

Finally, if the number under the square root sign is less than 0 this means there is no solution or real roots.  If the number under the square root is equal to 0 this means there is only one solution and really root and lastly, if the number is greater than 0 there is two solutions and two real roots.

In this case, the number under the square root is -8 which is less than 0 so this means, there is no solution or real roots to this quadratic equation.

Using the discriminant is helpful because we can determine how many solutions or real roots there are without solving the quadratic equation.