The unknown is how many girls and boys are in the class.
        
             
        
        
        
Answer: 8y4+25y3+60y2+10y+7
Step-by-step explanation:
(y2+3y+7)(8y2+y+1)
=(y2+3y+7)(8y2+y+1)
=(y2)(8y2)+(y2)(y)+(y2)(1)+(3y)(8y2)+(3y)(y)+(3y)(1)+(7)(8y2)+(7)(y)+(7)(1)
=8y4+y3+y2+24y3+3y2+3y+56y2+7y+7
=8y4+25y3+60y2+10y+7
hope this helps!:)
 
        
             
        
        
        
Answer:
A
12+7x=a
x=days
a=amount of money
B 12+7x=a
Step-by-step explanation:
7(18)=126
12+126=a
138=a
 
        
                    
             
        
        
        
The dimensions of the prism can be 2x, 2x+3 and x+6.
We first factor out the GCF of the trinomial.  The GCF of the coefficients is 2.  Each term has an x in common as well, so the GCF is 2x.
Factoring out the 2x, we have
2x(2x²+15x+18).
To factor the remaining trinomial, we find factors of 2*18=36 that sum to 15.  12*3 = 36 and 12+3 = 15.  We split up 15x into 12x and 3x:
2x(2x²+12x+3x+18)
Now we group together the first two terms in parentheses and the last two:
2x((2x²+12x)+(3x+18))
Factor out the GCF of the first group:
2x(2x(x+6)+(3x+18))
Factor out the GCF of the second group:
2x(2x(x+6)+3(x+6))
Factoring out what these have in common,
2x(x+6)(2x+3)