A square is shown below. Which expression can be used to find the area, in square units, of the shaded triangle in the square? A square with a side length of 6 units is shown. A diagonal is drawn with one section shaded inside the figure. (5 points) a fraction 1 over 4 ⋅ 6 ⋅ 6 b fraction 1 over 2 ⋅ 3 ⋅ 3 c fraction 1 over 4 ⋅ 3 ⋅ 3 d fraction 1 over 2 ⋅ 6 ⋅ 6