Question

find the value of y from figure

Answer 1

2y+y=90
3y=90
y = 90/3
y = 30

Answer 2

given:angel COB =90°
therefore,angel COB =90°(ANGLES ON A STRAIGHT LINE)
now,COD+COA=90°(COMPLEMENTARY ANGLES)
=y+2y=90°
=3y=90°.
=y=30°