Question

please teach me how to
solve
a-b=2
a+b=2

Answer 1

you could set \[a=b+2\]

then substitute it for a in the other equation.

Answer 2

Or you can just add the two equations.

Answer 3

a-b = 2
+ a+b = 2
=======
2a + 0 = 4

Answer 4

Then you can find a, and plug into one of the equations to solve for b.