Question

In the adjoining figure ABCD is a trapezium. If angle A : angle D=5:7, B= (3x+11)° and angle C= 5x-31)°, then find all the angles of the trapezium​

Answer 1

Answer:

A=75°

B=86°

C=94°

D=105°

Explanation:

Let A=5y andD=7y

A+D=180° [property of trapezium]

=>5y+7y=180°

=>y=15

Therefore, A=75° andD=105°

Also B+C=180° [property of trapezium]

=>3x+11+5x-31=180°

=>8x-20=180°

=>8x=200°

=>x=25

Therefore, B=(3×25)+11=86° and C=(5×25)-31=94°