Hi! can you explain how to do this problem and why? i appreciate it!

The ksp expression for the system pbcl2(s) pb+2(aq) + 2 cl-(aq) is: [pbc12][pb+2][2cl-] [pb+2][cl-]2 [pb+2][2cl-]2 [pbcl2][pb+2][cl-]2 [pb+2][2cl-]2[pbcl2]

Find and simplify an expression for the area of five rows of x squares with side lengths of x centimeters.

Write the rational number in lowest terms 99/-15