184k views
1 vote
Given that ZBCD and ZBCA form a straight angle, if ZABC measures 55

degrees and ZBCD measures 60 degrees, then the measure of ZBAC is
degrees.

Given that ZBCD and ZBCA form a straight angle, if ZABC measures 55 degrees and ZBCD-example-1
User Tjollans
by
6.9k points

1 Answer

2 votes

Answer:

Angle BAC is 5 degrees.

Explanation:

It's easiest if you just annotate you diagram as you find each angle. You can do this in lots of different ways, but this is how i got there.

So to find BAC, you need to find ABC and BCA. After you find these two, its just a matter of subtraction, which is simple.

We already know ABC = 55 degrees.

So now we have to find BCA:

1) They told us that BCD is 60 degrees and that its sitting on a straight line

2) From this we can find that BCA is 120 degrees, because a straight line is 180 degrees. 180 -60 = 120 degrees.

Now that we have both ABC and BCA, we can find BAC:

1) The angles of all triangles add up to 180 (idk why, its just how it is)

2) So, if we do 180 - BCA - ABC, we should get BAC

3) So, 180 - 55 - 120 = 5 degrees

Sorry if the explanation was really long, its a bit weird to explain it all in words. Hope it helped : )

User Ngoan Nguyen
by
5.7k points