The length of AD is 5 units. so, option A is the correct answer.
<h3>What is the Pythagoras theorem?</h3>
The Pythagoras theorem states that the square of the longest side must be equal to the sum of the square of the other two sides in a right-angle triangle.
The length of DC is given as 13 units.
The length of AC is given as 12 units. We can see that angle D is a right angle, so the triangle will be a right-angle triangle.
by Pythagoras theorem;
Hence, the length of AD is 5 units. so, option A is the correct answer.
Learn more about Pythagoras theorem;
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