The isosceles_triangle command takes three arguments and an optional fourth. The three mandatory arguments are two points A and B and an angle θ.
isosceles_triangle returns and draws the isosceles triangle
ABC, where AB and AC are equal sides and
θ is the angle from AB to AC.
Input:
Output:
The optional argument needs to be a variable name,
which is assigned to vertex C.
Input:
Output:
Input:
Output: