So you want to make one of the equations equal to one of the placeholders exg y=x+3
so we have
x+y=2 and
-2x+y=2
I chose to make -2x+y=2 equal to y so
-2x+y=2
add 2x to both sides
y=2+2x
subsitute 2+2x for y in x+y=2
x+2+2x=2
add like terms
3x+2=2
subtract 2 from both sides
3x=0
x=0
subsitute x=0 in x+y=2
0+y=2
y=2
x=0
y=2
2 and -12 are the coordinates of p
The price after the 25% would be $15
Or it will be $45 off