Ok sooooooooooo
Lets say your two fractions are
13/26 and 20/40
you can divide the bottom number by the top one and if you get the same answer for both then they are equivalent. For these you get 2 for both, which means they are equivalent.
another example would be if your fractions are
2/5 and 4/10
You can say well 2*2 equals 4 And 5*2 equals ten so these are equivalent fractions.