Answer: x = 12
Step-by-step explanation:
The tickmarks indicate which segments are the same length. On the left side, the single tickmark segments are the same length, and the same can be said about the double tickmarks segments as well. Because of this, the segment x cuts the diagonal sides in half.
The segment x is known as a midsegment of the triangle. It is half as long as the parallel side of 24 units. So x = (1/2)*24 = 12.