Question 252211: u^2-2uv-63v^2
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x^2+2xy-24y^2
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u^2-2uv-8v^2
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u^2-2uv-8v^2
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u^2-3uv-40v^2
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x^2+50x+625
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x^2-8xy+16y^2
Answer by jim_thompson5910(35256) (Show Source):
You can put this solution on YOUR website! I'll do the first two to get you started.
# 1
Looking at we can see that the first term is and the last term is where the coefficients are 1 and -63 respectively.
Now multiply the first coefficient 1 and the last coefficient -63 to get -63. Now what two numbers multiply to -63 and add to the middle coefficient -2? Let's list all of the factors of -63:
Factors of -63:
1,3,7,9,21,63
-1,-3,-7,-9,-21,-63 ...List the negative factors as well. This will allow us to find all possible combinations
These factors pair up and multiply to -63
(1)*(-63)
(3)*(-21)
(7)*(-9)
(-1)*(63)
(-3)*(21)
(-7)*(9)
note: remember, the product of a negative and a positive number is a negative number
Now which of these pairs add to -2? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to -2
| First Number | Second Number | Sum | | 1 | -63 | 1+(-63)=-62 | | 3 | -21 | 3+(-21)=-18 | | 7 | -9 | 7+(-9)=-2 | | -1 | 63 | -1+63=62 | | -3 | 21 | -3+21=18 | | -7 | 9 | -7+9=2 |
From this list we can see that 7 and -9 add up to -2 and multiply to -63
Now looking at the expression , replace with (notice combines back to . So it is equivalent to )
Now let's factor by grouping:
Group like terms
Factor out the GCF of out of the first group. Factor out the GCF of out of the second group
Since we have a common term of , we can combine like terms
So factors to
So this also means that factors to (since is equivalent to )
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Answer:
So factors to
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# 2
Looking at we can see that the first term is and the last term is where the coefficients are 1 and -24 respectively.
Now multiply the first coefficient 1 and the last coefficient -24 to get -24. Now what two numbers multiply to -24 and add to the middle coefficient 2? Let's list all of the factors of -24:
Factors of -24:
1,2,3,4,6,8,12,24
-1,-2,-3,-4,-6,-8,-12,-24 ...List the negative factors as well. This will allow us to find all possible combinations
These factors pair up and multiply to -24
(1)*(-24)
(2)*(-12)
(3)*(-8)
(4)*(-6)
(-1)*(24)
(-2)*(12)
(-3)*(8)
(-4)*(6)
note: remember, the product of a negative and a positive number is a negative number
Now which of these pairs add to 2? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to 2
| First Number | Second Number | Sum | | 1 | -24 | 1+(-24)=-23 | | 2 | -12 | 2+(-12)=-10 | | 3 | -8 | 3+(-8)=-5 | | 4 | -6 | 4+(-6)=-2 | | -1 | 24 | -1+24=23 | | -2 | 12 | -2+12=10 | | -3 | 8 | -3+8=5 | | -4 | 6 | -4+6=2 |
From this list we can see that -4 and 6 add up to 2 and multiply to -24
Now looking at the expression , replace with (notice combines back to . So it is equivalent to )
Now let's factor by grouping:
Group like terms
Factor out the GCF of out of the first group. Factor out the GCF of out of the second group
Since we have a common term of , we can combine like terms
So factors to
So this also means that factors to (since is equivalent to )
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Answer:
So factors to
The rest of the problems are all similar to these two. So I'll let you finish up.
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