Which would the phrase "the difference between a number and 5" look like as a variable expression?

Super ultra mega important if you can answer this correctly i will give you 100 points but if you don't answer it correctly you'll get a big report. so stay aware and have a nice day!

He expression 2(l + w) is used to calculate the perimeter of a rectangle, where l is length and w is width. if the length is fraction 2 over 3 unit and the width is fraction 1 over 3 unit, what is the perimeter of the rectangle in units? fraction 2 over 3 unit 1 unit 1fraction 2 over 3 units 2 units

When only separate discreet points are graphed it is called?