SOLUTION: How do we determine the number of real roots of an equation? can you determine the number of real solutions in the following equations? 1. x^2 - 5x = 0 2. x^2 + 2x + 8

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Question 423756: How do we determine the number of real roots of an equation?
can you determine the number of real solutions in the following equations?
1. x^2 - 5x = 0
2. x^2 + 2x + 8 = 0

Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
# 1


From we can see that , , and


Start with the discriminant formula.


Plug in , , and


Square to get


Multiply to get


Subtract from to get


So the discriminant is


Since the discriminant is greater than zero, this means that there are two real solutions.

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# 2

From we can see that , , and


Start with the discriminant formula.


Plug in , , and


Square to get


Multiply to get


Subtract from to get


So the discriminant is


Since the discriminant is less than zero, this means that there are two complex solutions.


In other words, there are no real solutions.


If you need more help, email me at jim_thompson5910@hotmail.com

Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you

Jim

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