Pretend these are coordinates that you can use to find the slope of the line.
(10, 40) and (15, 60). Fit these into the slope formula to find the slope of the line you are looking for:
[tex]m= \frac{60-40}{15-10} [/tex] and the slope is 4. Now use one of the points and the slope of 4 to solve for b, the y-intercept:
40 = 4(10) + b so b = 0. The equation of the line then is y = 4x + 0 or just
y = 4x
