A line segment has endpoints at (5 ,1 ) and (3 ,9 ). The line segment is dilated by a factor of 5 around (2 ,2 ). What are the new endpoints and length of the line segment?

1 Answer
Feb 5, 2018

New end points A' color(brown)( ((17,-3)), B' color(brown)((7,37)

Length of the line segment vec(A'B') ~~ color(green)(41.23

Explanation:

Given : A(5,1), B(3,9), dilated around C (2,2) & dilation factor 5

To find : End points and length of line segment after dilation

vec(A'C) = 5 * vec(AC) or a' = 5a - 4c

a' = 5((5),(1)) - 4((2),(2)) = ((25),(5)) - ((8),(8)) =color(brown)( ((17),(-3))

vec(B'C) = 5 * vec(BC) or b' = 5b - 4c

b' = 5((3),(9)) - 4((2),(2)) = ((15),(45)) - ((8),(8)) = color(brown)( ((7),(37))

vec(A'B') = sqrt((17-7)^2 + (-3 -37)^2) ~~ color(green)(41.23