The value of a is D)73 I think because 180-107 since a straight line is 180 u just subtract the angle from it. hope this helps.
Answer: Lol your in collage I don't believe it anyway the answer is 20 min on the dot
I would compute sqrt(1 + 160pi^2) first to get approximately 39.75093337
Add this to 1 and we have 40.75093337
Then divide over 2pi to get a final approximate result of 6.48571248
So x = 6.48571248 is one approximate solution
In short, I computed 
only focusing on the plus for now.
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If you were to compute 
you should get roughly -6.167402596 as your other solution. Each solution can then be plugged into the original equation to check if you get 0 or not. You likely won't land exactly on 0 but you'll get close enough.
1) (-7,2)
y=2, -x+4=11, -x=11-4=7, x=-7
2) (-3,4)
-x+2y=11
y=4, -x+8=11, -x=3, x=-3
3) (1,6)
-x+2y=11
y=6, -x+12=11,-x=-1, x=1
