Hey there!
To find the unit rate, or slope, we can use the rise over run formula. Rise is the change in y, and run is the change in x.
Since one of the values is the origin, or (0, 0), it will be easy to find the changes in these values.
The change in y is 15 and the change in x is 6.
15 ÷ 6 = 2.5
The unit rate is 2.5.
Hope this helps!