Question

tell me about the sum place ​

Answer 1

12.in triangle aob and cod

angle aob=cod ( vertically opposite angles)

angle oab=ocd ( alternate angles)

triangles similar by aa similarity

as we know that ratio of triangles is equal to two sides

ratio of triangles= (AB/CD) ²

=(3CD/CD)²

=(3/1) ²

=9:1