Lisa has a certain amount of money. she spent 39 dollars and has 3/4 of the original amount left. how do you write this equation?

Let’s call the amount of money she started with “m”.

What this problem is saying is that “taking away 39 from m is equivalent to taking 3/4 of m.” What do “taking away 39 from,” “equivalent to,” and “3/4 of” translate to mathematically?