B
The measure of ZDAB equals 110° The
measure of ZACB equals 20°.
What is mZ ABC?
D
A
Enter your answer in the box

Given

¯¯¯¯¯¯¯¯¯

D

A

C

is a straight line, we can say its full measurement is 180°. If we know a segment of this angle,

∠

D

A

B

, is 105°, we can know that the other segment

∠

B

A

C

must equal 75, since

105

+

75

=

180

.

Once we've found the measure of

∠

B

A

C

to be 75°, and given the measure of

∠

A

C

B

to be 35, we can then find the measurement of

∠

A

B

C

.

Since we know that the sum of any triangle's angles is 180°, we can then use these known measurements as I said above.

75

+

35

+

m

∠

A

B

C

=

180

110

+

m

∠

A

B

C

=

180

m

∠

A

B

C

=

70