Is a number that represents part of a whole or part of a set

The cost c, in dollars, for bananas depends on the weight w,in pounds, of the bananas. this situation is represented by the function rule c=0.5w (graph each function rule.tell whether the graph is continuous or discrete)

Find the value of x for which abcd must be a parallelogram -9-6x x-30

Asap! i'm not good math and i'm lost.