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## Properties of Triangles

Given a triangle with side lengths of 5, 12, and 14, is the largest angle in the triangle acute, right, or obtuse? Geometric knowledge helps us deduce much about triangles from limited information. See more

# Sum of Angles

In the above triangle, the blue angle is $$30^\circ$$ and the green angle is $$70 ^ \circ$$. What is the measure of the yellow angle (in degrees)?

In the above triangle, the blue angle is $$30^\circ$$, the green angle is $$80 ^ \circ$$, and the purple angle is $$45 ^ \circ$$. What is the measure of the yellow angle?

In the above diagram, the purple angle at $$Z$$ equals $$\color{purple}{ 144}^\circ$$ and the blue angle at $$Y$$ equals $$\color{blue} {111} ^ \circ$$. What is the measure of the green angle at $$X$$?

Note: The diagram is not drawn to scale.

In the above diagram, $$\color{blue} {\angle CAD=30^\circ}, \color{purple}{\angle ACD=80^\circ}$$ and line $$\overline{BD}$$ is a bisector of $$\angle ADC$$. What is $$\color{green}{\angle CBD}$$ in degrees?

In the above diagram, what is $$\color{green} {\text{green angle}}$$ in degrees?

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