Question

Assume that the number of defective basketballs produced is related by a linear equation to the total number produced. Suppose that 6 defective balls are produced in a lot of 200, and 15 defective balls are produced in a lot of 300.

Answer 1

you have two points: (200,6) and (300,15)

So, just use the two-point form of the line:

y-6 = (9/100)(x-200)