First you take the 128 and subtract it from 180. You then take the angle that’s vertical from it and place the number (52) and you add 52 + 24 to get 76. After that you take 76 and subtract it from 180 to get 104. X=104
The 1:3 ratio means that the distance from A to the point is 1/4 of the distance from A to B.
The difference of y-coordinates is 10-8 = 2. 1/4 of that is 2·1/4 = 1/2, so the point of interest will have y-coordinate 8 + 1/2 = 8 1/2. This apparently corresponds to the first selection:
... (6 1/2, 8 1/2)
I've uploaded a photo with the answer because it's too hard to do this out on the computer.
The y-intercept would be (0,0) so your equation would be y=(-x)+0, or y=(-x)
