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i tried graphing this but i keep getting the points wrong

 Feb 21, 2018
 #1
avatar+128079 
+2

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 :

 

 

 

 

 

cool cool cool

 Feb 21, 2018
edited by CPhill  Feb 21, 2018
 #2
avatar+128079 
+2

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 :

 

 

 

cool cool cool

 Feb 21, 2018

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