Answer:
[tex]x=z[/tex]
Step-by-step explanation:
[tex]x+y=z......(1)\\x=x+y....(2)\\\text{From equation(2), }x=x+y\text{ so you may write only }x\text{ in place of }x+y\text{ in }\\\text{equation(1).}\\\\\text{So }x+y\text{ in equation(1) becomes }x\text{.}\\\therefore\ x=z[/tex]