The term "closed" in math means that if you take two items from a set, do some operation, then you'll always get another value in the same set (sometimes you may get the same value as used before). For example, adding two whole numbers leads to another whole number. We therefore say "the set of whole numbers is closed under addition". This applies to integers as well because integers are positive and negative whole numbers. So we can say that integers are closed under addition.
Integers are not closed under division. Take two integers like 2 an 5 and divide: 2/5 = 0.4 which is not an integer. Integers don't have decimal parts.
The set of whole numbers is {0,1,2,3,...} and we can subtract the two values 1 and 2 to get 1-2 = -1. The order matters here. Subtracting a larger value from a smaller leads to a negative. The value -1 is not in the set of whole numbers. So we can say that whole numbers is not closed under subtraction
Finally, the set of irrational numbers is closed under addition. Adding any two irrational numbers leads to another irrational number. For instance, pi+sqrt(2) = 3.142 + 1.414 = 4.556; I'm using rounded decimals as approximate values. An irrational number is one where we cannot write it as a fraction of integers. Contrast that with a rational number in which we can write it as a fraction of integers. Example: 10 = 10/1 is a rational number.
So to fine slope you would use the formula down below:
rise/run
So use a graphed point, 0, -5 and you rise or count up quadrants up to a point and then horizontally move to when you find that point.
So from 0,-5 go up 9 vertically, and you would be on the 4
Go horizontal 3 spots and your on a designated point.
So the rise is four and the run is 3
So 4/3 is the slope
In the y= Mx + b equation you would set the equation like this:
y= 4/3 + -5
The m in this formula stands for the slop and the b stands for the y-intercept
The y-intercept is the point that is on the y-axis and where it starts.
Answer:

Step-by-step explanation:
By applying the concept of calculus;
the moment of inertia of the lamina about one corner
is:

where :
(a and b are the length and the breath of the rectangle respectively )


![I_{corner} = \rho [\frac{bx^3}{3}+ \frac{b^3x}{3}]^ {^ a} _{_0}](https://tex.z-dn.net/?f=I_%7Bcorner%7D%20%3D%20%20%5Crho%20%5B%5Cfrac%7Bbx%5E3%7D%7B3%7D%2B%20%5Cfrac%7Bb%5E3x%7D%7B3%7D%5D%5E%20%7B%5E%20a%7D%20_%7B_0%7D)
![I_{corner} = \rho [\frac{a^3b}{3}+ \frac{ab^3}{3}]](https://tex.z-dn.net/?f=I_%7Bcorner%7D%20%3D%20%20%5Crho%20%5B%5Cfrac%7Ba%5E3b%7D%7B3%7D%2B%20%5Cfrac%7Bab%5E3%7D%7B3%7D%5D)

Thus; the moment of inertia of the lamina about one corner is 
15x + 18y ≥ 120 would be the inequality