We will have a system of equations, and we are going to solve it by using substitution. Let's make the equations. x+y+z=2100 z+y=x Since y and z are equal, I think it is easier for us to have them as one variable for now. Let the value of z and y be a. These are the equations now. x+2a=2100 2a=x Since the second equation is giving the value of x, let it replace the value of x also in the first equation. 2a+2a=2100 4a=2100 2100÷4= 525 so, x and y equal 525. Let's put this in our original equation. x+525+525=2100 x+ 1,050= 2,100 x= 1,050 So, x=1,050, y= 525 =z.
