Question

In parallelogram ABCD B - A = 40o

, Find all the angles of parallelogram ABCD.​

Answer 1

Step-by-step explanation:

in parallelogram ABCD angle A and angle B are adjacent angles, that is, angle A+ angle B= 180° (sum of adjacent angles of parallelogram is supplementary) (1)

and,

angle B- angle A= 40° (2)

from (1) and (2)

adding them both we get

<A +<B+ <B-<A= 180+40

=> 2<B = 220. ( cancelling <A)

=> <B = 220/ 2

<B= 110°

therefore angle A+ 110= 180

which gives angle A is 70°

in parallelogram opp. angles are equal

whuch gives, <A=<C= 70° and <B=<D= 110°