Analytical Geometry (Division of line segments)

AI Thread Summary
To find the coordinates of point P on line segment AB extended through B, the ratio of distances AP to BP is set at 2:1, leading to coordinates P(8,11). For part (b), where P is extended through A with the ratio reversed, the calculations would similarly apply, but the specific coordinates were not provided in the discussion. The method used involves the equation XP = X1 + R(X2 - X1), where R represents the ratio. The initial calculations for part (a) appear correct, but there may be confusion regarding the graphical representation of the point. The discussion emphasizes the importance of understanding the ratio and its application in analytical geometry.
at94official
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1. Here is the Problem:

A line passes through A(2,3) and B(5,7).
Find:
(a) the coordinates of the point P on AB
extended through B to P so that P is twice as far from A as from B;
(b) the coordinates if P is on AB extended through A so that P is twice as far from B as from A.

Homework Equations

:[/B]
To get the coordinates P, here is the equation i used:
XP=X1+R(X2-X1)

R is the Ratio of AP/AB

I'll do the same for Yp

The Attempt at a Solution

:
[/B]
So this is my attempt to solve the (a) P Coordinates.

AP = 2BP

R=AP/AB=2/1=2

X = X1+R(X2-X1)
X = 2+2(5-2)
X = 2+2(3)
X = 2+6
X = 8

For Y:

Y = 3+2(7-3)
Y = 3+2(4)
Y = 3+8
Y = 11

∴ (a)P (8,11)As i attempt to graph it. It seems like it is too much based on the problem. What did I miss?
 
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Your solution looks fine.
 
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