Answer:
40 degrees
Step-by-step explanation:
Angle ACO = 80 ( 180 - 100)
Angle CAO = 60 (180 - 120)
Angle AOC = 40 (180 - 80 - 60) (TOTAL DEGREES OF A TRIANGLE IS 180)
1-(1/5)= 4/5 or 28/35 if you multiply top and bottom by 5
Answer: BAHAHAHAHHA I ACTAULLY KNOW IT IT IS K=4
A must be parallel to b.
Proof:
∠3 = <span>∠13 (given)
</span>∠15 = <span>∠13 (vertically opposite angles are equal)
Since </span>∠13 = ∠3 and ∠13 = ∠15, ∠15 = <span>∠3
Then, a must be parallel to b (transverse line d cuts parallel lines producing converse alternate angles that are equal (ie </span>∠15 = <span>∠3))
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