This is a standard sort of problem, not really a conventional algebra problem, commonly seen in crossword puzzle books (most often, consisting of a long division problem).
Google “Word arithmetic” for many hits, giving hints and clues.
Here are two:
Verbal arithmetic - Wikipedia (Wikipedia)
Solving Word Arithmetics by Jim Loy.
Furthermore, (not mentioned in exactly this form at a few sites I looked at), do this:
Draw a 10 x 10 grid. Put all the digits across the top. Put all the letters used in the problem (typically, there will be ten of them) down the side. Like this:
|0|1|2|3|4|5|6|7|8|9|
--+-+-+-+-+-+-+-+-+-+-+
A | | | | | | | | | | |
--+-+-+-+-+-+-+-+-+-+-+
B | | | | | | | | | | |
--+-+-+-+-+-+-+-+-+-+-+
C | | | | | | | | | | |
--+-+-+-+-+-+-+-+-+-+-+
D | | | | | | | | | | |
--+-+-+-+-+-+-+-+-+-+-+
E | | | | | | | | | | |
--+-+-+-+-+-+-+-+-+-+-+
F | | | | | | | | | | |
--+-+-+-+-+-+-+-+-+-+-+
G | | | | | | | | | | |
--+-+-+-+-+-+-+-+-+-+-+
H | | | | | | | | | | |
--+-+-+-+-+-+-+-+-+-+-+
J | | | | | | | | | | |
--+-+-+-+-+-+-+-+-+-+-+
K | | | | | | | | | | |
--+-+-+-+-+-+-+-+-+-+-+
Use all the hints you can figure out, to narrow down what letters could stand for what digits. If you find that a certain letter CANNOT be a certain digit, then put an X in the box for that letter/digit. (Very first hint: Multi-digit numbers are never written with a leading zero. So every letter that appears as the left-most digit of any number in the puzzle CANNOT be 0.)
If you determine, for sure, that a certain letter IS a certain digit, put a circle in that box. And since a letter can’t be two different digits, and they never have two different letters for the same digit (that’s a standard rule for these sort of puzzles), when you put a circle, you can put X in the rest of that entire row and entire column.
Continue using whatever hints you can find. (See the various web sites for lists of hints to look for.) As you gather more information, ruling in or ruling out things in your grid, the grid itself helps you find still more hints to rule in or rule out.
Continue until solved.
Ever see those logic puzzles that begin like:
“Mary, Sam, Betty, and Paul go to a movie together.
Their last names are Jones, Turner, Sampson, and Roberts (but not necessarily in that order).
Their professions are Butcher, Baker, Candle-Stick Maker, and Indian Chief (again, not necessarily in that order).
Mary stood in line behind the Baker.
Betty is married to the Indian Chief.
Mr./Mrs. Sampson had to ask Sam for change for the movie ticket . . .”
And so on. You’re supposed to figure out correctly who’s who and what their jobs are.
You do it the same way . . .
Make grids, and put X’s and O’s to indicate what’s known for sure and what’s ruled out.
For example, the statement “Mary stood in line behind the Baker” tells you that Mary isn’t the Baker.
The line Betty is married to the Indian Chief tells you that Mary isn’t the Chief. And also (assuming conventional naming conventions . . .) Wait, this tells you that they aren’t using standard naming conventions, since there’s a married couple but they all have different last names. Oh well.
You get the idea.
Word arithmetic problems are approached the same way, with the grid and the clues you can find in the digits.