I believe it’s constructing angle bisectors
50-10=40 then you would divide 40 by 3 so... it would be 13 banana's.
The form of the line is given by y=mx +b
Where b is the y intercept of the line
That is the point where the line cuts the y axis
So here b= 1
SoEquation is Y=1/3 x +(1)
Answer in place of question mark is 1