The formula for the area of the triangle is A = 1/2bh (1/2•base•height).
Identify your base and height and substitute them into the formula. Since you did not include an image or info in which states the base and height, this is what I can say.
If the base and height are 5 and 12, the area would be 30 yds. (1/2 x 5 x 12)
If the base and height are 5 and 16, the area would be 40 yds. (1/2 x 5 x 16)
If the base and height are 12 and 16, the area would be 96 yds. (1/2 x 12 x 16)
