3.2=15.75+3.2d; find d

plz show work and then explain

D= -3.921875 first you subtract 15.75 from 3.2 which is -12.55 then divide that by 3.2

3.2d + 15.75= 3.2
3.2. -15.75 -15.75

-12.55

3.2d

d= -3.921875

You have to do the inverse operation, so you subtract 15.75 to 15.75 then you cross those out. Then you subtract 3.2 to 15.75 which equals -12.55. After that, you divide 3.2 to 3.2, cross those out, then divide -12.55 to 3.2 which equals -3.921875~