Question

find the missing side length.
assume that all intersecting sides meet at right angles.
include the correct unit in your answer.
12 yd
15 yd
6 yd
9 yd
8 yd
?

Explanation:

Step1: Analyze the horizontal sides

The sum of the shorter horizontal sides should equal the longer horizontal side.
$$12 + 8$$

Step2: Calculate the missing side

Subtract the known horizontal side from the sum of the shorter horizontal sides.
$$12 + 8-9$$
$$=20 - 9$$
$$=11$$

Answer:

11 yd