Just so you know, there is a difference between the variables X and x.

Can you solve this now?

Given two points and , the slope of the line going through them may be calculated as

To get the rest of the equation for the line you can use the slope-intercept form:

Plug in either point and the slope you just calculated and solve for b.

I am personally against numbers written in this form, though I fully understand why they are useful. But I find that they rather confuse things by the time a student reaches their first Algebra course.

Anyway, I would convert these numbers to improper fractions:

You should be able to finish this now.

Someone else is going to have to help you with the last problem.

-Dan