Julia got a delivery order. She took some time to get ready, and then she rode her bike at a constant speed. The table compares the distance to you made (in kilometers) and the time since she got the order (in minutes and parentheses.

Solution
For this case we have the following info given:
Distance Time (minutes)
5 40
7 52
9 64
Then we want to find the time to travel 1 km so we can set up the following equation:
y= mx + b
m = represent the time to ride 1km
b= represent the fixed value
40 = 5m +b
52 = 7m +b
64 = 9m +b
52-40 = 7m-5m +b-b
12 =
________________
For example if m = 6 then b = 10
b=40 -5*6 = 10
Then we can conclude that for this case the answer is:
6 minutes