A skating rink charges a group rate of $9 plus a fee to rent each pair of skates. A family rents 7 pairs of skates and pays a total of $30. What does "X" represent?

Plz me plzzzzzzz i need and plz delte this after answer

Martin likes to make flower bouquets that have 3 daffodils and 4 tulips per vase. a daffodil has a mass of d grams, a tulip has a mass of t grams, and the vase has a mass of u grams. the expression 5(3d + 4t + v) describes the mass of 5 bouquets. match each amount in the situation with the expression that represents it. situation expression number of bouquets mass of one bouquet mass of the tulips in one bouquet 4t mass of the daffodils in one bouquet 3d + 4t + v

Find the quotient. 50a2 – 98b2 -5a +7b