SOLUTION: 5x^2+3x+5=0 What is the discriminant

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Question 923970: 5x^2+3x+5=0
What is the discriminant
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
ax%5E2%2Bbx%2Bc=0%0D%0A%0D%0Ayou+have+%7B%7B%7B5x%5E2%2B3x%2B5=0 where a=5, b=3, and c=5
we can find roots using quadratic formula x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ , and the expression used to find the discriminant D is the expression located under the radical in the quadratic formula
In a quadratic equation, the discriminant helps tell you the number of real solutions to a quadratic equation.
if b%5E2-4%2Aa%2Ac%3E0++ there are two real solutions, if the discriminant is a perfect square the roots are rational, otherwise, they are irrational
if b%5E2-4%2Aa%2Ac%3C0++-> no real solutions, two imaginary (complex) solutions
if b%5E2-4%2Aa%2Ac=0++-> one real solution
D=b%5E2-4%2Aa%2Ac++
in your case
=> D=3%5E2-4%2A5%2A5++ => D=9-100++=> D=-91++

in your case, D%3C0-> no real solutions, two imaginary (complex) solutions

let's see it on a graph:

+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+5x%5E2%2B3x%2B5%29+