Since AOB is the righ angle triangle as written AO is perpendicular to OB, so we can say angle AOB =90 Degree ...simultaneously we can write like this as well: AOC + BOC = AOB .....so AOC + BOC = 90 Degree and as given in question AOC = 2x-5 and BOC = x-10....we can equate the same....(2x-5) + (x-10) =90 ....solving it further .... 3x-15 = 90 .... 3x=75.....x = 25 hence the answer is 25.
In the figure, AO is perpendicular to OB, find angle AOC and angle BOC ?