Answer: x=4 and BC=20
STEPS:
Set the equation for AC and DF equal to each other then solve for x. 
2x+7=5x-5
Eliminate the -5 by adding it to both sides.
2x+12=5x
Move the x to one side by subtracting 2x from both sides.
12=3x
Isolate the x by dividing both sides by 3
4=x
EF=5x which means BC=5x
5(4)= 20 
So BC= 20
        
             
        
        
        
Chi would have two thousand nickels because if 100 nickels is 5% and 100 divided 5 is 20 so a 100 times 20 is 2000
        
             
        
        
        
Answer:
<u>multiply</u> the base and <u>add </u>the exponents
 
        
             
        
        
        
A polynomial function of least degree with integral coefficients that has the
given zeros  
Given 
Given zeros are 3i, -1  and 0
complex zeros occurs in pairs. 3i is one of the zero 
-3i is the other zero
So zeros are 3i, -3i, 0 and -1
Now we write the zeros in factor form 
If 'a' is a zero then (x-a) is a factor 
the factor form of given zeros 

Now we multiply it to get the polynomial

 polynomial function of least degree with integral coefficients that has the
given zeros  
Learn more : brainly.com/question/7619478