16.4k views
0 votes
If the angle A and B is given to me in a rumbas how do I find angle B

If the angle A and B is given to me in a rumbas how do I find angle B-example-1
User Znarf
by
8.7k points

1 Answer

4 votes

The values of angle A and B are 56⁰ and 132⁰ respectively.

How to calculate angle A and B.

From the figure

Given that ABCD is a parallelogram , then

Opposite angles are equal. If angle A is equal to angle C, and angle B is equal to angle D, where ABCD is a parallelogram.

7) 4y - 8 = 2y +20(opposite angles equal)

4y - 2y = 20 + 8

2y = 28

y = 28/2

= 14

<A = 4y -8

Substitute y = 14 into the expression 2y - 8 to find angle A

4(14) - 8

56-8 = 48⁰

8) Consecutive (adjacent) angles are supplementary, meaning the sum of two consecutive angles is always 180 degrees.

angle A + angle B = 180⁰

48 + B = 180

B = 180 - 48

= 132⁰

The values of angle A and B are 56⁰ and 132⁰ respectively.

User Kristian Duske
by
8.4k points