There are 72 members of the show choir. There are 6 more boys than girls in choir. Write a model of a system for the above situation

Question

Write a system of equations that can be solved using substitution 

Answer 1

X= Boy

Y= Girl

 

X+Y=72

 

but you know that 

 

X= 6 more than girl = 6+Y

 

so since

 

X+Y=72

 

and X= 6+Y, plug in X in the X+Y=72 and you get

 

6+ Y+ Y = 72

 

6+2Y=72

 

Getting Y by itself you would firs get 6 to the other side by subtracting

 

6-6+2Y=72-6

 

2Y=66

 

then divide both side by 2 to get Y by itself

 

2Y/2=66/2

 

Y= 66/2 =  answer