The graph below is a coordinate system based on 60
angles. It was
drawn on isometric paper.
The marked points are (6, 2), (6, 5) and (9, 2). When joined they
form an equilateral triangle.
The following 5 sets of points are also triangles.
A. (1, 13), (6, 8) and (6, 13).
B. (1, 1), (3, 3) and (7, 1).
C. (12, 1), (17, 1) and (8, 9).
D. (1, 10), (5, 2) and (6, 6).
E. (7, 5), (15, 4) and (7, 11).
What kinds of triangles are they?
Can you work out any of the angles at the vertices?
