Question

Plz HELP fast!!

Answer 1

$4b+2-Bill's\ blocks\\8b-5-Ron's\ blocks\\\\4b+2+8b-5=\\12b-3\\\\Total\ number\ of\ blocks\ is\ 12b-3$

Answer 2

Bill =  4b + 2.
Ron = 8b - 5.

Bill + Ron =  (4b + 2) + (8b - 5).
                =  4b + 8b + 2 - 5.
                = 12b  - 3.

That's the expression for the total number of blocks used by both Bill and Ron.