1、8x=6y
2、x+y= 10
3、Z=8x+6y
X=3y/4 can be obtained from the equation 1, and then x=30/7 and y=40/7 can be obtained by substituting it into equation 2.
Substituting X and Y into Equation 3, we can get Z=30/7×8+40/7×6=68.57 km.
This is junior high school math, right? I haven't written such a basic company for years, and I almost forgot all about it.