When you equate one thing with another, you say that they are both the same. You might equate indulging in a hot fudge sundae with giving up on your body entirely, but I would disagree.
To equate means to make things equal, and it’s a useful word because this is something people do all the time. They equate strong political views with fascism, they equate having lots of money with good taste, and they equate popularity with goodness. Remember, though, that just because you equate one thing with another does not mean that they really are the same! As you have no doubt noticed, equate has the Latin root equ that means "equal, level," so look there if you need a reminder as to its meaning.