Solve a(x − b) − 2k = l for a. someone explain, i do not want just an answer, i would like to understand.

You want to isolate a for when solve the equation for a

a(x − b) − 2k = L

you get everything away from a
add 2k to both sides of the equation


a(x − b) − 2k + 2k = L + 2k

since
− 2k + 2k is 0, then the left side is

a(x − b) = L + 2k

then we divide both sides by x - b to cancel out x - b on the leftside

a = (L+2k)/(x − b)

or