Drag each expression to the correct location in the equation. Not all expressions will be used. Determine the two rational expressions whose difference completes this equation.
1 + 2
12 36
12 + 6
r2 + 61
12 + 36
x2 + x + 6
x(x - 6)(x + 6)

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?