The sum of two numbers is 45 and their difference is 5 what are the 2 numbers

Can someone me with this problem . show your work .

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]

Which of the following scenarios demonstrates an exponential decay