The given equation is ,
→ y= 15 x+ 10, where y =total score on math quiz, and x= number of question answered
As this is the equation in two variables representing straight line.
As x> 0, ∴ number of questions attempted is always positive
So, as y, marks obtained will be also positive number.
By, taking positive integral values of x and y we can plot it's graph.
for example, if number of questions answered=2,4,6
then marks obtained=40, 70, 100