SOLUTION: If figure ABCD below is a parallelogram, what is the value of y? a. 120 b. 90 c. 60 d. 30 Link to image http://152.46.13.240/MoodleContent/SATprep/Math%20Unit%206/Post%20A

Algebra ->  Parallelograms -> SOLUTION: If figure ABCD below is a parallelogram, what is the value of y? a. 120 b. 90 c. 60 d. 30 Link to image http://152.46.13.240/MoodleContent/SATprep/Math%20Unit%206/Post%20A      Log On


   

Question 983320: If figure ABCD below is a parallelogram, what is the value of y?
a. 120
b. 90
c. 60
d. 30
Link to image
http://152.46.13.240/MoodleContent/SATprep/Math%20Unit%206/Post%20Assessment/parallelogram%202.gif
Found 2 solutions by macston, Danielshinmath:
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
.
Since AB and CD are parallel, angles B and C are supplementary, so:
4x degrees + 2x degrees=180 degrees
6x degrees=180 degrees
x=30 degrees
.
Opposite angles of a parallelogram are congruent so angle B is congruent to angle D, so:
measure of angle B=4x degrees
measure of angle D=y
angle B=angle D
4x=y (x=30 degrees from above)
4(30 degrees)=y
120 degrees=y
ANSWER: (a.) 120 degrees

Answer by Danielshinmath(31) About Me  (Show Source):
You can put this solution on YOUR website!
A
Explanation: 2 adjacent angles in a parallelogram will always equal 180 degrees. This means that 4x+2x=6x will equal 180 degrees. This means x=30. Then, 2x+y must equal 180 So that means 60 (2x) +y=180. y=180-60=120
Answer: A, 120