Solve Isosceles Triangle in Coordinate System

In summary, you can find 3 paths that the point R can trace, a line and 2 circles. The distance between P and Q is not an integer, but you can find an integer value for n such that x+y-n=7.
  • #1
thereddevils
438
0

Homework Statement



I will to explain this without a diagram. Consider a coordinate system(1st quadrant) where the x and y-axis both stop at 7 units (i mean the boundary), there are two points P(3,3) and Q(4,4). How many points can R be positioned such that PQR is an isosceles triangle.

Homework Equations





The Attempt at a Solution



I got 6.
 
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  • #2
Well I had quite a few and started counting them... Eventually I counted up to infinite different possible points :-p

There are actually 3 paths the point R can trace, a line and 2 circles. See if you can find them.
 
  • #3
thereddevils said:

Homework Statement



I will to explain this without a diagram. Consider a coordinate system(1st quadrant) where the x and y-axis both stop at 7 units (i mean the boundary), there are two points P(3,3) and Q(4,4). How many points can R be positioned such that PQR is an isosceles triangle.

Homework Equations





The Attempt at a Solution



I got 6.
Then you haven't given all the information. Are you talking about a "mesh" where the points must have integer components? As you give it, any point on the perpendicular bisector of PQ works and there are an infinite number of them.
 
  • #4
HallsofIvy said:
Then you haven't given all the information. Are you talking about a "mesh" where the points must have integer components? As you give it, any point on the perpendicular bisector of PQ works and there are an infinite number of them.

yeah sorry, it must be of integer components where you can precisely represent that particular point on the plane.

My 6 points are

(5,2) , (2,5) , (6,1) , (1,6) , (7,0) , (0,7)
 
  • #5
thereddevils said:
must be of integer components where you can precisely represent that particular point on the plane.

Yet the distance between P and Q is not an integer.
Anyway, this means we have the two equations

[tex]\sqrt{(x-4)^2+(y-4)^2}=n[/tex]

[tex]\sqrt{(x-3)^2+(y-3)^2}=n[/tex]

where n is an integer, to solve simultaneously.
After simplifying, we find the perpendicular bisector of PQ to be the line x+y-7=0
Now just use all possible integer values of x and y such that x+y=7.

I don't know if I should scrap the idea of the point R can trace that are circles rather than this line, because that means we have to use a non-integer value for another length.
 
  • #6
Mentallic said:
Yet the distance between P and Q is not an integer.
Anyway, this means we have the two equations

[tex]\sqrt{(x-4)^2+(y-4)^2}=n[/tex]

[tex]\sqrt{(x-3)^2+(y-3)^2}=n[/tex]

where n is an integer, to solve simultaneously.
After simplifying, we find the perpendicular bisector of PQ to be the line x+y-7=0
Now just use all possible integer values of x and y such that x+y=7.

I don't know if I should scrap the idea of the point R can trace that are circles rather than this line, because that means we have to use a non-integer value for another length.

sigh.. 8 points then including (4,3) , (3,4)
 

FAQ: Solve Isosceles Triangle in Coordinate System

What is an isosceles triangle?

An isosceles triangle is a triangle with two sides of equal length and two equal angles.

How do you solve an isosceles triangle in a coordinate system?

To solve an isosceles triangle in a coordinate system, you will need to know the coordinates of all three vertices of the triangle. Then, you can use the distance formula and Pythagorean theorem to find the lengths of the sides and angles of the triangle.

What is the distance formula?

The distance formula is a mathematical formula used to find the distance between two points on a coordinate plane. It is expressed as √[(x2 - x1)^2 + (y2 - y1)^2], where (x1, y1) and (x2, y2) are the coordinates of the two points.

How do you use the Pythagorean theorem to solve an isosceles triangle?

The Pythagorean theorem states that in a right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the other two sides. To solve an isosceles triangle using the Pythagorean theorem, you will need to find the length of the base and then use the theorem to find the length of the other two sides.

What are some real-life examples of isosceles triangles?

Some real-life examples of isosceles triangles include the roofs of many houses, the sails of sailboats, and the wings of many airplanes. They are also commonly found in architecture, bridges, and other structures.

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