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Which of the following describes the given shape?
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A) Isosceles triangle, B) right triangle, C) scalene triangle, D) obtuse triangle, and E) equilateral triangle.
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So that we can actually decide which one of these triangles actually describes our shape, we’ll look at a definition for each.
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If we start with an isosceles triangle, well, an isosceles triangle is a triangle with two equal sides.
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A right triangle is a triangle, where one angle is 90 degrees.
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A scalene triangle is a triangle that has no sides of the same length.
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An obtuse triangle is one that has one obtuse and that’s an angle greater than 90 degrees and two acute angles.
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And then, finally, an equilateral triangle is one that has three equal sides.
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Okay, great, so we have definitions for each of our triangles.
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And these aren’t exhaustive actually because for each of our types of triangles, there are other relationships to do with angles et cetera, which will also be apparent.
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But however, it’s gonna help us with solving this problem.
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So if we look back at our triangle, we see these two lines and what they tell us is that these two sides are actually equal.
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So therefore, we know that actually our triangle has two equal sides.
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So therefore, answer A isosceles triangle best describes our given shape.