math proof of an isosceles triangle

[deanie]

I need help proving a triangle is isosceles with NO LESS than seven steps and I can only think of two. I have a triangle a-bottom left base angle b- vertex angle c-right base angle. So <bac ~ <bca is a given. I have an angle bisector (d). But I dont know how to prove it in seven steps. Help????

 

[dtoepel]

Proving a triangle is isoscelese means proving two sides are equal. You are given that two angles are equal. Think of a theorem you have that relates opposite sides of equal angles in a triangle.
Dave