Answer:
D. rectangle
Explanation:
The slopes of 2 lines are perpendicular when they are the negative reciprocal of each other. In this case, that is true, because 3 is the negative reciprocal of -1/3 and vice versa. This means it's either a rectangle or a square.
The lengths of the lines are not all the same, meaning it cannot be a square.
Therefore, the best name for the quadrilateral MATH is rectangle.
I hope this helped.