ON lesson 3-4 there were a couple of questions I didn’t get. This is one of them d-14.25=-23.9

I didn’t get it because it’s a negative so I thought you would add it. I asked Anna and she got a different answer then me so I asked Mr.B and he told me that sense it’s a negative it goes  my right which  it to the zero. Once i under stood that I relised that my answer was wrong and Anna did it right. I felt like a fool but now i under stand it.