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If the discriminant of a quadratic equation is equal to -8, which statement describes the roots?

A.) There are two complex roots.
B.) There are two real roots.
C.) There is one real root.
D.) There is one complex root.

2 Answers

3 votes

Answer:

There are two complex roots

User Darewreck
by
7.1k points
3 votes

Keywords

quadratic equation, discriminant, complex roots, real roots

we know that

The formula to calculate the roots of the quadratic equation of the form
ax^(2) +bx+c=0 is equal to


x=\frac{-b(+/-)\sqrt{b^(2)-4ac}}{2a}

where

The discriminant of the quadratic equation is equal to


b^(2)-4ac

if
(b^(2)-4ac)> 0 ----> the quadratic equation has two real roots

if
(b^(2)-4ac)=0 ----> the quadratic equation has one real root

if
(b^(2)-4ac)< 0 ----> the quadratic equation has two complex roots

in this problem we have that

the discriminant is equal to
-8

so

the quadratic equation has two complex roots

therefore

the answer is the option A

There are two complex roots

User Paul Shannon
by
7.7k points