There is no single solution but there is a group of solutions also known as the interval.

This can be written with an interval.

Hope this helps.
r3t40
Hello,
P(x)=150*1.07^x
==>ln(P(x)/150)=x*ln(1.07)
==>x=(ln(P(x)-ln(150))/ln(1.07)
If you know how much is P(x) then you have the answer.
-2[3x-b-2x+x-3b]
-2[(3x - 2x + x) + (-b -3b)]
-2[2x - 4b]
-4x + 8b