Question

Name or state the postulate, property, definition or theorem that justifies the statement.

$MW+WN=MN$.

Short answer

The postulate that justifies the statement is the segment addition postulate.

Step-by-step solution

Step 1. State the segment addition postulate.

The segment addition postulate:

If B lies on a line between two points Aand C, then their intersection is a line.

Then, the distance between the points satisfies the condition AB + BC.

Step 2. State the explanation.

Using the segment addition postulate:

If W lies on a line between two points M and N, then MW + WN = MN.

Thus, the statement is justified.

Step 3. State the conclusion.

Therefore, the statement is justified by the segment addition postulate.