What does it mean to isolate the variable?

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

1jessica's home town is a mid-sized city experiencing a decline in population. the following graph models the estimated population if the decline continues at the same rate. select the most appropriate unit for the measure of time that the graph represents. a. years b. hours c. days d. weeks

Find the solution of each of the following.