Could be wrong but since given the smaller quadrilateral is similar to to larger one, by definition the ratio of there corresponding sides would be congruent. Length of 5 of ec is to 10 of bc as the length of fe (6) is to the length of ab would be 12
120÷100= 1.2
24÷1.2= 20
24 is 120% of 20
it would be y = -12/5. Hes the work. hope this helps!
