I'm having a hard time on this problem. Plz help. Will mark brainliest.
Find the value of y.
-20
-87
-31
-42
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Answer:
Step-by-step explanation:
We know: opposite angles in a parallelogram have the same measure.
Therefore we have the equation:
[tex]x+y=87+y[/tex] subtract y from both sides
[tex]x=87[/tex]
We know: the sum of the angle measures in the triangle is 180°.
Therefore we have the equation:
[tex]42+(x+y)+20=180[/tex] subtitute x = 87
[tex]42+87+y+20=180[/tex]
[tex]149+y=180[/tex] subtract 149 from both sides
[tex]y=31[/tex]