Problem: The polygon(s) formed by , and , is (are):
Answer Choices:
A. an equilateral triangle
B. an isosceles triangle
C. a right triangle
D. a triangle and a trapezoid
E. a quadrilateral
Solution:
The given lines intersect in the three points , and . These three points are the vertices of a triangle with , each of length , and , so that is the correct choice.