SOLUTION: how to we solve the following equation to find the complex number/roots? x^2-8x+30=0 I was sick and was absent when my class went over complex numbers and roots so Im not fam

Algebra ->  Complex Numbers Imaginary Numbers Solvers and Lesson -> SOLUTION: how to we solve the following equation to find the complex number/roots? x^2-8x+30=0 I was sick and was absent when my class went over complex numbers and roots so Im not fam      Log On


   

Question 672619: how to we solve the following equation to find the complex number/roots?
x^2-8x+30=0
I was sick and was absent when my class went over complex numbers and roots so Im not familiar with it.
Thanks(:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
how to we solve the following equation to find the complex number/roots?
x^2-8x+30=0
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Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B-8x%2B30+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%28-8%29%5E2-4%2A1%2A30=-56.

The discriminant -56 is less than zero. That means that there are no solutions among real numbers.

If you are a student of advanced school algebra and are aware about imaginary numbers, read on.


In the field of imaginary numbers, the square root of -56 is + or - sqrt%28+56%29+=+7.48331477354788.

The solution is , or
Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-8%2Ax%2B30+%29

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If you want to know the number and type of roots, look at what it says about the Discriminant.
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For these [real] solutions to exist, the discriminant should not be a negative number.