find the determinant

Question

if  det   a    c 

            b    d   = 5

what is det   2a    3d

                   2b    3c    

Answer 1

The second determinant value is (2a)(3c) - (2b)(3d) 

and the first determinant = ad - bc which = 5.

 

Are you sure that you have the letters in the right places in each determinant?  I don't see how you can solve this.