Question

Write the name or statement of the definition, postulate, or theorem that justifies the statement about the diagram.

If D is the midpoint of $\overleftrightarrow{AB}$, then $AD=\frac{1}{2}AB$.

Short answer

The name of the theorem which justifies the statement about the given diagram is midpoint theorem.

Step-by-step solution

Step 1. Observe the given diagram.

The given diagram is:

Step 2. Write the midpoint theorem.

The midpoint theorem states that if a point B is the midpoint of $\overleftrightarrow{AC}$, then $AB=\frac{1}{2}AC$.

Step 3. Write the name of the theorem that justifies the statement about the given diagram.

From the given diagram it can be noticed that the point D is the midpoint of $\overleftrightarrow{AB}$, therefore $AD=\frac{1}{2}AB$.

Therefore, the name of the theorem that justifies the statement about the given diagram is midpoint theorem.