5. Isosceles and Equilateral Triangles
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Start by considering the Isosceles Triangle Theorem and use the Triangle Angle-Sum Theorem.
x=13
We are given a triangle and a pair of its interior angle measures. We also know that two of the side lengths are congruent.
Classification of Triangles | |
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Scalene Triangle | A scalene triangle is a triangle in which all three sides have different lengths. |
Isosceles Triangle | An isosceles triangle is a triangle that has two congruent sides and two base angles with the same measure. |
Equilateral Triangle | An equilateral triangle is a triangle in which all the sides are congruent. |
Acute Triangle | An acute triangle is a triangle where all angles are less than 90^(∘) or π2. |
Obtuse Triangle | An obtuse triangle is a triangle with exactly one an angle whose measure is greater than 90^(∘) or π2. |
Right Triangle | A right triangle is a specific type of triangle that contains one angle of 90^(∘). |
Since the given triangle has two congruent sides, triangle EHG is an isosceles triangle. Then, to find x, we will first consider Isosceles Triangle Theorem.
Isosceles Triangle Theorem |
If two sides of a triangle are congruent, then the angles opposite those sides are congruent. |
Using the theorem, let's label the congruent angles.