Please solve I need help brain list to correct and first

Umm.. just started this 2day and its not on my notes(p′︵‵。)

Arectangle has an area of 54 square feet. if the length is 3 feet more than the width, find the dimensions of the rectangle.

Which formula finds the probability that a point on the grid below will be in the blue area? p(blue) = total number of squares number of blue squares number of blue squares p(blue) = total number of squares number of blue squares p(blue) = number of white squares