Y - x = 28
y + x + 156

I think is −  

2

3(9y+52)

Step-by-step explanation:

a variable is any characteristics, number, or quantity that can be measured or counted. a variable may also be called a data item. hope i !

step-by-step explanation:

step 1: solve one of the equations for one of the variables. let's solve the first equation for y:

step 2: substitute that equation into the other equation, and solve for x.

step 3: substitute x = 4 x = 4 x=4 into one of the original equations, and solve for y.