coordinate geometry get points on perimeter and point within

[i1c2z3y4l5]

i need to know the formula to get the coordinates that are on the perimeter and within the shape of square and rectangle. does anyone know that?

lets say square coordinates of (1,1) , (1,3) , (3,3) , (3,1)

points on perimeter would be (1,2) , (2,1) , (2,3) , (3,2) excluding the actual coordinates above.

points within shape would be (2,2)

[jlucero]

I'm not familiar with any equation that would help you here, and I know that no formula is necessary to answer any questions on the GMAT. It's far more important that you be able to make those four points on a coordinate plane and look to see what points would be inside/outside the shape.

The one equation you should be familiar with is y=mx+b. With this equation, you could plug in 2 points that make a line and determine that line's slope (m) and y-intercept (b). From those, you could find any other points on that line.