Red line slope=3/4
Blue line slope=2/3
Of means multiplication
So

And then simplify the numerator ad denominator
=

And simplify the numerator and denominator again
=

And we are finally left with the answer which is
I believe it’s B.) sorry if I’m wrong!!!!
Term to be added is: + 121/4
t^2 + 11t + 121/4
(t + 11/2) (t + 11/2)
180-50 would be 130.
The missing angle is 130 degrees