5d+2(2-d)=3(1+d)+1
The trick in all these types of problems is to simplify the equation on both sides and isolate the variable by some mathematical operation(s).
Let's do the first part.....
Distribute the 2 across (2-d) to get 4 - 2d and on the other side distribute the 3 across (1+d) to get 3 + 3d.
So, we have
5d + 4 - 2d = 3 + 3d +1
Combine like terms on both sides
3d + 4 = 3d + 4
Notice that we have the SAME thing on both sides!!
This means that "d" can take on any value we want it to. In other words, "d" can be any real (or even "imaginary") number that we can think of. If we confine ourselves to the real number system, d takes on all values from negative to positive infinity!!
I suspect that this was one of those "special" algebra problems designed to make you think. (Don't you just hate those??)
Hope this helps.
