Question

In the figure lines PQ,MN,ST intersect each other at O. Determine the value of y.

Answer 1

5y+2y180-(2y+5y)=180

Answer 2

as shown in pic angle at point o = 5y opp angle of point o = 5y ( VOA)
: Asa = 180 = sum of all sides
180 = 5y +5y +2y
180 = 12y
y = 180 / 12
y = 15