6. Inequalities in Two Triangles
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Focus on triangle △ YZW.
m∠ ZUY>m∠ ZUW
Let's mark the angles we are asked to compare.
Notice that ZY=ZW. This means that triangle △ ZYW is isosceles, so angles ∠ ZWY and ∠ ZYW are congruent.
We can now use the Triangle Angle Sum Theorem in triangles △ ZUY and △ ZUW to find the measure of the angles we are asked to compare. m∠ ZUY+45+40=180 &⟹ m∠ ZUY=95 m∠ ZUW+55+40=180 &⟹ m∠ ZUW=85 We are now ready to write the inequality we were asked to find. 95>85 ⇓ m∠ ZUY> m∠ ZUW