SOLUTION: please help factor each expression. 7x^2 - 30x + 8

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Question 173936: please help factor each expression.
7x^2 - 30x + 8
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
7x%5E2+-+30x+%2B+8
I'll use the quadratic formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a+=+7
b+=+-30
c+=+8
x+=+%28-%28-30%29+%2B-+sqrt%28+%28-30%29%5E2-4%2A7%2A8+%29%29%2F%282%2A7%29+
x+=+%2830+%2B-+sqrt%28900+-+224+%29%29%2F14+
x+=+%2830+%2B-+sqrt%28676%29%29%2F14+
x+=+%2830+%2B+26%29%2F14+
x+=+56%2F14
x+=+4
and
x+=+%2830+-+26%29%2F14+
x+=+4%2F14
x+=+2%2F7
These are the roots. The factors are
x+-+4+=+0
and
x+-+%282%2F7%29+=+0
If I multiply both sides by 7,
7x+-+2+=+0
The factors are
%28x+-+4%29%287x+-+2%29 answer