SOLUTION: I am in need of help Solve by using the quadratic formula X^2=5x+8 Thank you

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Question 93535: I am in need of help
Solve by using the quadratic formula X^2=5x+8
Thank you
Found 2 solutions by checkley75, chitra:
Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
x^2-5x-8=0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x=(5+-sqrt[-5^2-4*1*-8])/2*1
x=(5+-sqrt[25+32])/2
x=(5+-sqrt57)/2
x=(5+7.55)/2
x=12.55/2
x=6.275 answer.
x=(5-7.25)/2
x=-2.25/2
x=-1.125 answer.

Answer by chitra(359) About Me  (Show Source):
You can put this solution on YOUR website!
The given equation is:

x%5E2+=+5x+%2B+8

This can be written as :


x%5E2+-+5x+-+8+=+0+

Comparing the above equation with the standard equation, that is ax%5E2+%2B+bx+%2B+c+=+0+

We see that a = 1, b = -5 and c = -8

The quadratic formula is given by:


x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

substituting for the values of a,b and c we get:

+x+=+%285+%2B-+sqrt%2825+%2B+32%29%29%2F%282+%2A+1%29+


x+=+%285+%2B-+sqrt%2857%29%29%2F%282%29+


Thus the solution.