Download Reflecting over a point that is not the origin again use slope

Reflecting over a point that is not the origin ­ again use slope
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POINT SYMMETRY­ Take the center point as the point of reflection and reflect every point on the figure through that point. You must get the same figure back (on top of itself)
***if you turn it upside down it looks the exact same
Ex of shapes with Point Symmetry
Z N S SWIMS Ex of shapes withOUT Point Symmetry
F
G
J
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6.5 Translations ‐ each point slides/shifts the same number in the same direction Symbol: T
Ex) Ta,b(x, y) = (x+a, y+b)
*The number you add to x is the horizontal movement, negative means left and positive means right.
(you are adding a to x and b to y if they are positive numbers, you are subtracting if they are negative)
*The number you add to y is the vertical movement, positive is up and negative is down.
***The Properties of a Translation are the same properties as Line Reflection and Point Reflection***
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**You must always
label the axes and
use a ruler!
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Translational symmetry: All of the figures move in the same direction and the same distance from the one before it
Ex: NOT translational Symmetry: (not the same distance apart)
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Homework: pg 232 #15, 16 AND pg 236‐237 #3, 11
STUDY FOR YOUR QUIZ TOMORROW!!!
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6.8­Dilations
Dilations: to enlarge or reduce
Symbol: Dk(x,y) = (kx,ky) (you are multiplying the x & y by a number)
Example: D 4(6,2) = (24, 8)
D1/2(10,­2) = ***The Properties of a Translation are the same properties as Line Reflection and Point Reflection EXCEPT....DISTANCE does not stay the same***
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