Question

In parallelogram BCDE if m C
B
70
50°
E

Answer 1

m∠DEB = 130°

Explanation:

Key: Only two angles are congruent because of the parallelogram

Since m∠EBC = 50° m∠CDE = 50°

Then we are missing m∠BCD and m∠DEB

50 + 50 + m∠BCD + m∠DEB = 360°

100 + m∠BCD + m∠DEB = 360°

m∠BCD + m∠DEB = 360 - 100

m∠BCD + m∠DEB = 260

m∠BCD + m∠DEB = 260/2

m∠BCD + m∠DEB = 130°

m∠BCD and m∠DEB = 130°

Answer 2

`x=130`

Explanation:

Opposite angles of a parallelogram are equal

EBC = 50° while, CDE = 50° too

Area of a parallelogram is 360°

Suppose, BCD to be x too, & form an equation:

`50+50+x+x=360`

`100+2x=360`

`2x=360-100`

`2x=260`

`x=260/2`

`x=130`

{CHECK:
`130+130+50+50=360^(o)`}