Find a line in the rectangle from 0.0 to some point

In summary, the conversation discusses finding a line or diagonal in a rectangle where for every point in the shaded area below the line, x is greater than y. The dimensions of the rectangle are given as H=1 and L=2. The attempt at a solution involves finding a point (1,1) on the line y=1, but there is confusion about why this point is necessary. The conversation also mentions a joint p.d.f. problem involving random variables (X, Y) and finding the constant value of the p.d.f. on a rectangle and the probability of X being greater than or equal to Y. Finally, there is a mention of the impossibility of answering the question without knowing the location of the rectangle in the
  • #1
TheMathNoob
189
4

Homework Statement


There is a rectangle in the x-y plane with dimensions H=1, L=2. Find a line or diagonal in the rectangle in which for every point in the shaded area below that line x>y.

Homework Equations

The Attempt at a Solution


The line has to intersect a point in y=1 in which x>y. This point would be (1,1). But I do not get why.
 
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  • #2
TheMathNoob said:

Homework Statement


There is a rectangle in the x-y plane with dimensions H=1, L=2. Find a line or diagonal in the rectangle in which for every point in the shaded area below that line x>y.

Homework Equations

The Attempt at a Solution


The line has to intersect a point in y=1 in which x>y. This point would be (1,1). But I do not get why.
Is there a pitcher associated with this problem that hasn't been attached?
 
  • #3
SteamKing said:
Is there a pitcher associated with this problem that hasn't been attached?
Suppose that the joint p.d.f. of a pair of random variables (X, Y) is constant on the rectangle where 0≤x ≤2 and 0≤y ≤1, and suppose that the p.d.f. is 0 off of this rectangle.

a. Find the constant value of the p.d.f.on the rectangle=1/2.
b. Find Pr(X≥Y)
 
  • #4
TheMathNoob said:
The line has to intersect a point in y=1 in which x>y. This point would be (1,1). But I do not get why.
Not sure I understand your question. I wouldn't worry about the distinction between > and >= here.
 
  • #5
TheMathNoob said:

Homework Statement


There is a rectangle in the x-y plane with dimensions H=1, L=2. Find a line or diagonal in the rectangle in which for every point in the shaded area below that line x>y.
It is impossible to answer this without knowing where the rectangle is. The same size rectangle placed at different places in the plane will give different answers.

2. Homework Equations

The Attempt at a Solution


The line has to intersect a point in y=1 in which x>y. This point would be (1,1). But I do not get why.
 

FAQ: Find a line in the rectangle from 0.0 to some point

1. What is the purpose of finding a line in a rectangle from 0.0 to some point?

The purpose of finding a line in a rectangle from 0.0 to some point is to determine the equation of a straight line that passes through the origin (0.0) and a given point within the rectangle. This can help in understanding the relationship between the x and y coordinates of the point and how they relate to the origin.

2. How is the equation of a line in a rectangle from 0.0 to some point determined?

The equation of a line in a rectangle from 0.0 to some point is determined using the slope-intercept formula, y = mx + b, where m is the slope of the line and b is the y-intercept. The slope can be calculated by taking the difference between the y coordinates of the given point and the origin and dividing it by the difference between the x coordinates. The y-intercept can be found by substituting the slope and coordinates of the given point into the equation.

3. Can this method be used for any rectangle?

Yes, this method can be used for any rectangle as long as the given point is within the boundaries of the rectangle. The rectangle can be positioned at any location on a coordinate plane and the line can still be found using the same method.

4. What if the given point lies on the x or y axis?

If the given point lies on the x-axis, the equation of the line will be y = 0x + b, where b is the y-intercept. If the given point lies on the y-axis, the equation of the line will be x = a, where a is the x-intercept. In both cases, the line will still pass through the origin (0.0).

5. Is it possible for two different lines to pass through the origin and the same given point in a rectangle?

No, it is not possible for two different lines to pass through the origin and the same given point in a rectangle. The line found using this method is unique and is the only line that can pass through both the origin and the given point.

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