In the diagram, triangles ABC and CBD are isosceles. The perimeter of \triangle{CBD} is 19, the perimeter of \triangle{ABC} is 20, and the length of BD is 7. What is the length of AB?
Answer Choices
A. 5
B. 6
C. 7
D. 8
E. 9
In the diagram, triangles ABC and CBD are isosceles. The perimeter of \triangle{CBD} is 19, the perimeter of \triangle{ABC} is 20, and the length of BD is 7. What is the length of AB?
Answer Choices
A. 5
B. 6
C. 7
D. 8
E. 9