Question

The measure of ∠DAB equals 110º. The measure of ∠ACB equals 20º.

What is m∠ABC?



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Answer 1

`m\angle ABC = 90^\circ`

Explanation:

We are given the following information in the question:

`\angle DAB = 110^\circ\\\angle ACB = 20^\circ`

We have to find the measure of
`\angle ABC`

By exterior angle sum property, we can write

`m\angle DAB = m\angle ABC + m\angle ACB`

Putting the values, we get:

`m\angle DAB = m\angle ABC + m\angle ACB\\110 =  m\angle ABC + 20\\m\angle ABC = 90^\circ`

Answer 2

90 degrees

Angle DAB and BAC are supplementary so 110 + 70 =180. (<BAC is 70)

Triangle ABC is 180 degrees so if you add 20 and 70 you get 90. The last angle, <ABC must be 90 degrees.