Help lol

Answer asap and if you do you will get brainliest. catherine buys a gallon of ice cream from the store. after taking it home, she eats a fifth of a gallon of ice cream. her sister eats some of the ice cream as well. if two-thirds of the original amount of ice cream is left, then what fraction of a gallon of ice cream did her sister eat?

What is a correct first step in solving the inequality-4(3-5x)> -6x+9

Rewrite the polynomial -9x5 + 36x4 + 189x3 in factored form.