SOLUTION: Solve the quadratic equation by the formula: x^2-8x+14=0

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Question 2855: Solve the quadratic equation by the formula:
x^2-8x+14=0
Answer by xcentaur(357) About Me  (Show Source):
You can put this solution on YOUR website!
Compare with standard form
ax%5E2%2Bbx%2Bc=0
We get,
a=1,b=8,c=14.
Formula for Quadratic Equations is:

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

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

x+=+%28-8+%2B-+sqrt%28+8%5E2-4%2A1%2A14+%29%29%2F%282%2A1%29+
Then step by step we get,

x+=+%28-8+%2B-+sqrt%28+64-4%281%29%2814%29+%29%29%2F2+

x+=+%28-8+%2B-+sqrt%28+64-56+%29%29%2F2+

x+=+%28-8+%2B-+sqrt%28+8+%29%29%2F2+
Therefore we have 2 values possible for x,which are:
x+=+%28-8+%2B+sqrt%28+8+%29%29%2F2+ OR x+=+%28-8+-+sqrt%28+8+%29%29%2F2+

Note that square root of 8 is: 2.828
On further solving as per formula,we get possible values of x as:
(-8+2.828)/2 OR (-8-2.828)/2
Resulting in rounded off values of x as:
-2.586 OR -5.414
Therefore,
Solution Set={-2.586,-5.414}
Hope you followed this,
Best of luck.