Not really sure what you mean by compare. The only thing I can think of is the y intercept is generally a good point to start from to count the rise/run
8/13 = 0.6153
y = cos-1(0.6153)
y = 52.0
I'm not totally sure if this is what you mean or if this is.
y = cos(8/13) = 0.9999 which to the nearest tenth is 1.0
Hey can you take another pic
