Question

ABCD is a trapezium in which AB is parallel to CD. The diagonals AC and BD intersects at O. If OA = 6 CM and OC = 8cm
Then find the ratio of area of triangle AOD and area of triangle COD.
This question is from triangle similarity question of class 10

Answer 1

From D draw a perpendicular onto AC to meet AC at E,

Area of triangle AOD = 1/2 DE * OA ,  as  OA = base,  DE = altitude.

Area of triangle COD = 1/2 DE * OC ,  as  DE is the altitude from D onto base OC.

ratio of areas = AD / CD = 6/8 = 3/4

Answer 2

From D draw a perpendicular onto AC to meet AC at E,

Area of triangle AOD = 1/2 DE * OA ,  as  OA = base,  DE = altitude.

Area of triangle COD = 1/2 DE * OC ,  as  DE is the altitude from D onto base OC.

ratio of areas = AD / CD = 6/8 = 3/4