The expression you have is already in its simplest form. However, there is another way to write it.
m - n/4
This expression is the same as the original, apart from the fact that we wrote the division as a fraction.
Distance formula!!!!! yay i've done this umpth manytimes today for people so if you dont know distance formula is square root of (x1-x2)^2+ (y1+y2)^2.
0-(-7) -1-(-2)
7^2 + 1^2
49+1
sqr. root of 50
appx. 7.07 or the closest to it