Explain how you know - 5 and 1/5 are multiplicative inverse? I'm very stuck on this and need to get this math done

they are multiplicative inverses because to find the inverse of a number you change it from positive to negative or vice versa, and you have to change it to it's inverse. to do this you have to put it in fraction form if it isn't already (so 5 would be 5/1) and flip it (5/1 flipped would be 1/5)