B and C
0+11= +11
0-11= -11
Hope this helps
The length of line segment is the horizontal distance between two points
Suppose
a line has endpoints
The length of the line is
discount per tshirt=(originalprice-discountedprice)/numberofshirtssold
20 tshirts
originaprice=20*p=20p
discountedprice=20p-60
numberofshirtssold=20
discountpershirt=(20p-(20p-60))/20
discountpershirt=(20p-20p+60)/20
discountpershirt=(60)/20
discountpershirt=3
the discount per tshirt is $3.00 per shirt
The table and the graph is shown in the following picture
