SOLUTION: 3x^2 + 17x + 10? Whats the answer?

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Question 160318: 3x^2 + 17x + 10? Whats the answer?
Found 2 solutions by Edwin McCravy, Electrified_Levi:
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
How do you factor completely: 3x%5E2+%2B+17x+%2B+10? Whats the answer?

3x%5E2+%2B+17x+%2B+10

Multiply the 3, (coefficient of x%5E2 by the 10, 
(constant term), getting 30.

Write all the pairs of integers that have product 30

matrix%284%2C1%2C1%2A30%2C2%2A15%2C3%2A10%2C5%2A6%29

Beside them write their sums:



Pick out the one that has the sum 17, the coefficient of x.

matrix%281%2C2%2C2%2A15%2C2%2B15=17%29

Rewrite the 17 in

3x%5E2+%2B+17x+%2B+10

as %282%2B15%29

3x%5E2+%2B+%282%2B15%29x+%2B+10

Distribute and rewrite %282%2B15%29x as 2x%2B15x

3x%5E2+%2B+2x%2B15x+%2B+10

Factor x out of the first two terms:

x%283x+%2B+2%29%2B15x+%2B+10

Factor 5 out of the last two terms:

x%283x+%2B+2%29%2B5%283x+%2B+2%29 

Foctor %283x%2B2%29 out of each:

%283x+%2B+2%29%28x%2B5%29

Edwin

Answer by Electrified_Levi(103) About Me  (Show Source):
You can put this solution on YOUR website!
Hi, Hope I can help,
.
How do you factor completley:+3x%5E2+%2B+17x+%2B+10+? Whats the answer?
.
We can find the first part of the number, by finding factors of "3" (1, and 3)
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The first part of the answer is (3x )(x ), since all the numbers are positive we can put "+" in both of the factors
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(3x )(x ) = (3x + )(x + )
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Next, you need to find all factors of "10"
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Factors of 10: (1,10) and (2,5):Factors in order ( 1,2,5,10 )
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Next you have to multiply "3" and "1", by one of the two pairs of factors (10), the numbers we get will have to add up to "17"
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+3%281%29%2B1%2810%29+=+3+%2B+10+=+13+ Nope, we will switch the factors of "10"
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+3%2810%29%2B1%281%29+=+30+%2B+1+=+31+ Nope, we will use the other factors of "10"
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+3%282%29%2B1%285%29+=+6+%2B+5+=+11+ Nope, we will switch the factors of "10"
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+3%285%29%2B1%282%29+=+15+%2B+2+=+17+ True, we need to use the factors "5" and "2"
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We have to put the "5" and "2" in the right place in the answer (Since we got the answer by +3%285%29%2B1%282%29+=+15+%2B+2+=+17+, we will put the factors in opposite order that we did to find the addition answer)
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(3x + )(x + ) = (3x + 2 )(x + 5 )
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We can check our answers by multiplying the factors out, using the FOIL method
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+%283x+%2B+2+%29%28x+%2B+5++%29+ = +%28highlight%283x%29+%2B+2+%29%28highlight%28x%29+%2B+5++%29+ = +%28highlight%283x%29+%2B+2+%29%28x+%2B+highlight%285%29++%29+ = +%283x+%2B+highlight%282%29+%29%28highlight%28x%29+%2B+5++%29+ = +%283x+%2B+highlight%282%29+%29%28x+%2B+highlight%285%29++%29+ = +3x%28x%29+%2B+3x%285%29+%2B+2%28x%29+%2B+2%285%29+
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+3x%28x%29+%2B+3x%285%29+%2B+2%28x%29+%2B+2%285%29+ = +3x%5E2+%2B+15x+%2B+2x+%2B+10+ = +3x%5E2+%2B+17x+%2B+10+ ( Our answer)
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The two factors (Your answer) = +%283x+%2B+2+%29 and +%28x+%2B+5++%29+
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The simplified equation = +%283x+%2B+2+%29%28x+%2B+5++%29+=+0+
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Hope I helped, Levi