5. The Triangle Inequality
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Use the Triangle Inequality Theorem to form three inequalities true for the triangle.
x>0
We are given three expressions for measures of the sides of a triangle.
x+2, x+4, x+6
According to the Triangle Inequality Theorem, the sum of the lengths of any two sides of a triangle is always greater than the length of the third side. Using this theorem, we can write three true inequalities for this triangle.
| Inequality | Simplified | Solution Set |
|---|---|---|
| x+2+x+4 > x+6 | x>0 | x>0 |
| x+2+x+6 > x+4 | x > -4 | x>-4 |
| x+4+x+6 > x+2 | x>-8 | x>-8 |
Now we can graph the inequalities and find the set of common solutions.
As we can see, the lines overlap after 0. Therefore, the possible values of x are the following. x>0