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, 2023

Geometry Difficulty 1.4 Junior Find the answer Canada

In the diagram, $BCD$ is a
straight line segment.

The measure of $\angle ABC$ is

Pick one

Solution

Since $BCD$ is a straight line
segment, then $\$\angle$ BCD
$=180\degree\$.$

Therefore, $\$\angle$ ACB $=\angle BCD-\angle ACD=180\degree-75\degree=105\degree\$.$

Since the sum of the three angles in $\triangle ABC$ is $180\degree$ , then $\$\angle ABC=180\degree-105\degree-35\degree=40\degree\$.$

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.