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Geometry Difficulty 2.2 Junior Find the answer

What is the measure of the largest angle in PQR\triangle P Q R?

A number or a short expression. Spacing and $ signs are ignored.

Solution

Since the sum of the angles in a triangle is 180180^{\circ}, then 3x+x+6x=1803 x^{\circ}+x^{\circ}+6 x^{\circ}=180^{\circ} or 10x=18010 x=180 or x=18x=18. The largest angle in the triangle is 6x=6(18)=1086 x^{\circ}=6(18^{\circ})=108^{\circ}.

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