Question 181934: These need to be factored completely
30z^8 + 44z^5 +16z^2 Could it be 2z^2(3z^ + 2)(5z^3 +4)
24x² + 14xy +2y²
(m+n)(x+3) + (m+n)(5+5) Could it be (m+n+3)(x+y+5)
Solve using the principal of zero products
(x+ 1/7)(x-4/5) = 0
Find the x-intercepts for the graph of the equation
Y = x² + 4x -45 Could it be (-9,0,(5,0)
Factor by grouping
-36x² -30x + 36 Could it be -6(3x-2)(2x+3)
Answer by jim_thompson5910(35256) (Show Source):
You can put this solution on YOUR website! I'll do the first two, which will hopefully help you with the rest of the problems. If not, then repost.
# 1
Start with the given expression
Factor out the GCF
Now let's focus on the inner expression
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Looking at we can see that the first term is and the last term is where the coefficients are 15 and 8 respectively.
Now multiply the first coefficient 15 and the last coefficient 8 to get 120. Now what two numbers multiply to 120 and add to the middle coefficient 22? Let's list all of the factors of 120:
Factors of 120:
1,2,3,4,5,6,8,10,12,15,20,24,30,40,60,120
-1,-2,-3,-4,-5,-6,-8,-10,-12,-15,-20,-24,-30,-40,-60,-120 ...List the negative factors as well. This will allow us to find all possible combinations
These factors pair up and multiply to 120
1*120
2*60
3*40
4*30
5*24
6*20
8*15
10*12
(-1)*(-120)
(-2)*(-60)
(-3)*(-40)
(-4)*(-30)
(-5)*(-24)
(-6)*(-20)
(-8)*(-15)
(-10)*(-12)
note: remember two negative numbers multiplied together make a positive number
Now which of these pairs add to 22? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to 22
First Number | Second Number | Sum | 1 | 120 | 1+120=121 | 2 | 60 | 2+60=62 | 3 | 40 | 3+40=43 | 4 | 30 | 4+30=34 | 5 | 24 | 5+24=29 | 6 | 20 | 6+20=26 | 8 | 15 | 8+15=23 | 10 | 12 | 10+12=22 | -1 | -120 | -1+(-120)=-121 | -2 | -60 | -2+(-60)=-62 | -3 | -40 | -3+(-40)=-43 | -4 | -30 | -4+(-30)=-34 | -5 | -24 | -5+(-24)=-29 | -6 | -20 | -6+(-20)=-26 | -8 | -15 | -8+(-15)=-23 | -10 | -12 | -10+(-12)=-22 |
From this list we can see that 10 and 12 add up to 22 and multiply to 120
Now looking at the expression , replace with (notice adds up 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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So our expression goes from and factors further to
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Answer:
So completely factors to
# 2
Start with the given expression
Factor out the GCF
Now let's focus on the inner expression
------------------------------------------------------------
Looking at we can see that the first term is and the last term is where the coefficients are 12 and 1 respectively.
Now multiply the first coefficient 12 and the last coefficient 1 to get 12. Now what two numbers multiply to 12 and add to the middle coefficient 7? Let's list all of the factors of 12:
Factors of 12:
1,2,3,4,6,12
-1,-2,-3,-4,-6,-12 ...List the negative factors as well. This will allow us to find all possible combinations
These factors pair up and multiply to 12
1*12
2*6
3*4
(-1)*(-12)
(-2)*(-6)
(-3)*(-4)
note: remember two negative numbers multiplied together make a positive number
Now which of these pairs add to 7? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to 7
First Number | Second Number | Sum | 1 | 12 | 1+12=13 | 2 | 6 | 2+6=8 | 3 | 4 | 3+4=7 | -1 | -12 | -1+(-12)=-13 | -2 | -6 | -2+(-6)=-8 | -3 | -4 | -3+(-4)=-7 |
From this list we can see that 3 and 4 add up to 7 and multiply to 12
Now looking at the expression , replace with (notice adds up 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 )
------------------------------------------------------------
So our expression goes from and factors further to
------------------
Answer:
So completely factors to
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