5. The Triangle Inequality
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Use the Triangle Inequality Theorem.
No, see solution.
We have been given the following potential side lengths. 3 in. 4 in. 8 in. We will check whether these sides can form a triangle. In order to do that, we will use the Triangle Inequality Theorem. This theorem tells us that the sum of the lengths of any two sides of a triangle is greater than the length of the third side.
XY+YZ>XZ YZ+XZ>XY XZ+XY>YZ Applying this theorem to the given side lengths, we have three inequalities. I:3+4? >8& ⇒ 7 ≯ 8 II:4+8? >3& III:8+3? >4& Since the sum of one pair of side lengths is not greater than the third length, these side lengths will not form a triangle.