Explanation:
To find the area of a trapezoid, you can use the formula:
Area = (a + b) * h / 2
where a and b are the lengths of the two parallel sides, and h is the height (the perpendicular distance between the parallel sides).
In this case, the lengths of the parallel sides are 12 cm and 19 cm, and the height is 3 cm. So, we can plug these values into the formula:
Area = (12 cm + 19 cm) * 3 cm / 2
Area = 31 cm * 3 cm / 2
Area = 93 cm²
Therefore, the area of the trapezoid is 93 cm².