Frst one
Scale Factor 1/2 Dilation Center(-1, 1)
We need this formula
New Point ' = [ Old Point - Dilation Center ] * Scale Factor + Dilation Center
Remember that (a , b) - ( c, d) = ( a - c, b - d)
And C(a, b) = (Ca, Cb)
A' =
[ (-4, 4) - ( -1, 1)] * (1/2) + (-1, 1) =
(-3, 3)* (1/2) + (-1, 1) =
(-3/2, 3/2) + (-1, 1) =
(-5/2, 5/2)
B' =
[ (2, 4) - (-1, 1)]* (1/2) + (-1, 1) =
[ (3, 3) * (1/2) + ( -1, 1) =
(3/2, 3/2) + (-1, 1) =
(1/2, 5/2)
C' = [ (-4, 1) - (-1, 1) ] * (1/2) + (-1, 1) =
[ (-3, 0) ]* (1/2) + (-1, 1 ) =
(-3/2, 0) + (-1, 1) =
(-5/2, 1)
Here's a pic :
Second one
Scale factor = 1/2 Dilation Center = (8, -6)
A' =
[(-4, 4) - (8, - 6) ] * (1/2) + (8, - 6) =
[ (-12, 10] * (1/2) + (8, -6) =
(-6, 5) + (8, -6) =
(2, -1)
B' =
[ (4, 2) - (8, -6) ] *(1/2) + (8, -6) =
[ (-4, 8) ] * (1/2) + ( 8, -6) =
(-2, 4) + ( 8 , - 6)
(6, -2)
C' =
[ (-6, -4) - ( 8, -6) ] * (1/2) + (8, -6) =
[ (-14, 2) ] * (1/2) + (8, -6) =
(-7, 1) + ( 8, - 6)
(1, -5)
Here's a pic :