How to know when to increase or decrease the coordinates of an object when colliding with another?

Question

JavaScript

Here I tried to implement it, but one side is junk and the object is purposefully, uncontrollably moving through the other.
It should work like this:
If the object collided from above - subtract Y, if from below - add Y.
Similarly with X.
Thanks in advance.

if(blob.pos.x+blob.r/2+10 > block[i].pos.x && blob.pos.x < block[i].pos.x+blockbg.width+blob.r-10 && blob.pos.y > block[i].pos.y-blob.r+10 && blob.pos.y < block[i].pos.y+blockbg.height+blob.r-10) {
        mouseX = blob.pos.x;
        mouseY = blob.pos.y;
    }