Question

x - ( - y ) = x + y for the value x = 20, y = 17

Answer 1

20-(-17)=20+17
20+17=20+17
37=37

LHS=RHS.....

hope it helps you....

Answer 2

Putting the value of x and y in the equation x-(-y) =x+y
On the left hand side
x-(-y)
Putting the value of x and y
=20-(-17)
=20+17
=37