given that a/b=c/d, decide whether it is true or not that a/c=b/d.

Question

and how can i explain my reasoning?

Answer 1

given that a/b = c/d
then ad = bc

now divide both sides by cd to get
a/c = b/d as required

or

if we cross - multiply the first we had ad = bc
if we cross-multiply a/c = b/d we also get ad = bc
so it it true.

Answer 2

thank you