If a dvd player cost $180, how much would it be if it was 40% off

Hello from MrBillDoesMath!

See Discussion section below

Discussion:

We know that

m<1  = m<2          ("measure" of angle 1 = measure of angle 2)

                     and

m<3 = m< 4

Adding these two equations gives

m<1 + m<3 = m<2 + m<4

From the diagram,  m<1 + m<3 =  m<CWE and m<2+m<4= m<FZH. Substituting these in the above equation gives:

m<CWE = m<FZH

Regards,  

MrB