A line segment has endpoints at (2 ,1 )(2,1) and (6 ,2 )(6,2). The line segment is dilated by a factor of 4 4 around (2 ,1 )(2,1). What are the new endpoints and length of the line segment?

1 Answer
Feb 10, 2018

New end points coordinates of A ((2),(1)), B ((18),(5))

length of line segment ~~ color(green)(16.49

Explanation:

Given : A(2,1), B(6,2), dilated around C(2,1), dilation factor 4

To find the end points of the line segment and its length

vec(A'C) = 4 * vec(AC) or a' = 4a - 3c

a' = 4((2),(1)) - 3 ((2),(1)) = ((8),(4)) - ((6),(3)) = color(brown)(((2),(1))

vec(B'C) = 4 * vec(BC) or b' = 4b - 3c

b' = 4((6),(2)) - 3 ((2),(1)) = ((24),(8)) - ((6),(3)) = color(brown)( ((18),(5))

Length of the line segment using distance formula,

vec(A'B') = sqrt((2-18)^2 + (1-5)^2) ~~ color(green)(16.49