First find the slope between any two points:

Where

are the two points
So calculating the slope:

So the slope is

And our equation will be in the format of

where

and

So, now we have half of the equation:

Now to calculate b, we can plug in a point

and solve for b.
So

Lets use the point

So:

And then:

So our final equation is
Context clues and look it up! we are here for moral support
You can do addition and substraction operations with polynomials similarly as with simple real numbers.
First of all you have to open brackets and then you can add numbers (-7-4=-11). Then the result is following:
Y = 8x - 2.....slope here is 8. A parallel line will have the same slope.
The other line would be : y = 4 + 8x (or y = 8x + 4).....because they both have the same slope, which makes the lines parallel to each other