Grades 9-10 Video Solutions 2026-2026_9-10

Video Transcription

Video Summary

The transcript explains solving for the 10 equal angles by splitting the figure into a quadrilateral, triangle, and heptagon. Letting each equal angle be \(X\), the quadrilateral gives one angle as \(360 - 3X\). This matches an angle in the triangle, whose angles sum to 180. Then the heptagon’s interior angles sum to \(900\), leading to an equation involving seven \(X\) angles and two triangle angles. Solving the equation gives \(X = 108^\circ\). Therefore, each equal angle is <strong>108 degrees</strong>, and the correct answer is <strong>C</strong>.

Keywords

equal angles

quadrilateral

triangle

heptagon

108 degrees