Please help me with this one

Aparallelogram has two side lengths of 5 units. three of its sides have equations y = 0, y = 2, y = 2x. find the equation of the fourth side.

anyone? find the second, fifth, and ninth terms of a sequence where the first term is 65 and the common difference is -7. 72, 93, 121 72, 79, 86 58, 37, 9 58, 51, 44

If f(x)= sqrt4x+9+2, which inequality can be used to find the domain of f(x)?