Answer:
No
Explanation:
The reason for this is that the line is not increasing by 1.5. If we take the 2 y values which are 20 and 10. 20-10 is 10 and if we take the 2 x values and subtract them, we would get 30-15 which is 15. Now divide the y value and the x value (10/15) and we would get 0.66666.... Which is not 1.5. This was probably done because he mixed up the x values and y values which would be 15/10 and a common mistake when reading a coordinate plane. This does show a proportional relationship because the line is constant and therefore proportional. Hope this helps!