So (positive integer)-x-y can be negative
so to get a negative number as your result/answer, x+y must be greater than (positve integer) so for example
lets say (positive integer)=8
x+y must be greater than 8 to make the equation negative so
example
x=5
y=4
x+y=9
8-9=-1
Each student would get 1.6 brownies
Remember that the area of a square is just one of its sides squared.

where

is the area of the square

is one of the sides of the square
Unit square is a square whose sides have length 1, so lets use our formula to find the volume of one unit square:



We now know that each one of the squares has area 1 unit squared. Since there are 28 unit square in our figure, we are going to multiply the area of a unit square by 28 to find the area of our figure:
Area of the figure=

units squared
We can conclude that the area of the figure is 28 units squared.
step 2 would be 10
step 4 would be 10x-x = 9x =7
x = 7/9