SOLUTION: Factor completely. Show all work 7x2 + 11x – 30

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Question 299768: Factor completely. Show all work
7x2 + 11x – 30
Found 2 solutions by checkley77, josmiceli:
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
7x^2+11x–30
(7x-10)(x+3) ans.



Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
7x%5E2+%2B+11x+-+30
Use the quadratic formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a+=+7
b+=+11
c+=+-30
x+=+%28-11+%2B-+sqrt%28+11%5E2-4%2A7%2A%28-30%29+%29%29%2F%282%2A7%29+
x+=+%28-11+%2B-+sqrt%28+121+%2B+840+%29%29%2F14+
x+=+%28-11+%2B-+sqrt%28961%29%29%2F14+
x+=+%28-11+%2B+31%29%2F14
x+=+20%2F14
x+=+10%2F7
and, also
x+=+%28-11+-+31%29%2F14
x+=+-42%2F14
x+=+-3
The factors are:
%28x+-+10%2F7%29%2A%28x+-+%28-3%29%29+=+0
%28x+-+10%2F7%29%2A%28x+%2B+3%29+=+0
check:
Multiplying these, I get
x%5E2+-+%2810%2F7%29%2Ax+%2B+3x+-+30%2F7+=+0
Multiply both sides by 7
7x%5E2+-+10x+%2B+21x+-+30+=+0
7x%5E2+%2B+11x+-+30+=+0
OK