So we gots apolynomial equation that is 3rd degree and crosses x axis at x=-1, x=0 and x=2
the factors of a poly equation that passes through r1,r2,r3 is
(x-r1)(x-r2)(x-r3)
so
r1=-1
r2=0
r3=2
f(x)=(x-(-1))(x-0)(x-2)
f(x)=(x+1)(x)(x-2)
f(x)=x³-x²-2x
leading coefient is posiitve because 3rd degree equations that are postive go bottom left to top right
yah
actually that looks like the exact graph
both 
f(x)=(x+1)(x)(x-2)
and
f(x)=x³-x²-2x
are correct 
        
             
        
        
        
WHERES THE QUESTION IT WONT SHOW UP ON MY SCREEN POST IT AGAIN
        
             
        
        
        
$14.20 is the cost of each book
        
                    
             
        
        
        
Focus on triangles DFC and DFE:
- They are both right triangles because DF is perpendicular to EC
 - DC=DE
 - DF is a common side
 
So, the two triangles are congruent. It follows that CF=FE, and in particular

And since x=3, the length of EF is

 
        
             
        
        
        
Answer: XY = 8
Step-by-step explanation:
The diagram of the triangle XYZ is shown in the attached photo. 
XY=XZ. This means that two sides of the triangle are equal. Two angles are also equal. It means that the triangle XYZ is an isosceles triangle.
Since XY=XZ, then
2a = 5a - 12
Subtracting 2a from both sides of the equation, 
2a - 5a = 5a - 12 - 5a
-3a = -12
a = -12/-3
a = 4
Therefore, the length of XY is 2a = 2×4 = 8