Can someone me to solve this problem. $28 is 7 of what amount

This question awards 100 ! i really don’t want to fail i will also mark you !

Me asap on # : explain how factoring a trinomial, ax^2+ bx+ c, when a does not equal 1 different from factoring a trinomial when a = 1.

Express -5 2/5 as an improper fraction.