If you use the equation y-y1=m(x-x1) it would give you y-0=-1/4(x-2) which you would then have to simplify into slope intercept from rather than point slope form.
you do this by using the distributive property on the -1/4(x-2) which would give you y=-1/4x+1/2
All triangles have a total of 180° in them.
So to find x, simply take 50° and 100° from 180°:
x = 180 - 100 - 50
= 30°
So x = 30°, and thus option D
