Grades 9-10 Video Solutions 2010-Levels 9&10 Video Solutions 2010 problem12

Levels 9&10 Video Solutions 2010 problem12

Video Transcription

Video Summary

The question requires finding the measure of a marked angle in overlapping triangles. By analyzing the given angles, the missing angle is calculated using the properties of triangles and supplementary angles. A 330-degree angle implies a 30-degree angle for completion to 360 degrees. Right triangles, given their 20-degree angles, yield complementary 70-degree angles in adjacent spaces. The supplement of this 70-degree angle is 110 degrees. For the highlighted triangle, the sum of its angles (30, 110, and the unknown) must equal 180 degrees, leading to the answer: a 40-degree angle. Thus, the answer marked is B, 40 degrees.

Keywords

triangles

angles

supplementary

geometry

calculation