How do i write the slope (which i found using y2-y1/x2-x2) in slope intercept form (y=mx+b)?

In y = mx + b, m is the slope and b is the y-intercept.

So, first substitute the value: your found slope goes in the place of m

Then, find the y-intercept by, in addition to substituting your slope, replace x with the x value of your coordinate and y with the y value of your coordinate in the formula and solve for b

Hope this helps!