Respuesta :
Answer:
Substitution method.
Step-by-step explanation:
Using the substitution method is very easy, you have a system of equations like the next one:
x+y=7
x-y=3
So you clear one of them for one of the variable and then substitute that cleared variable in the other equation:
x=3+y
*x+y=7
*(3+y)+y=7
*3+2y=7
*2y=7-3
*2y=4
*y=2
That is hte method of substitution.