## Geometry: Common Core (15th Edition)

Using the Triangle Inequality Theorem, we need to see if the sum of each of the combinations of two sides is greater than the other side: $5 + 9 > 4$ --> This statement is true. $4 + 9 > 5$ --> This statement is true. $4 + 5 > 9$ --> This statement is false. A triangle cannot have these lengths for its sides because two of the sides added together are not greater than the third side.