4.1-4.3
How many lines of symmetry does this figure have?
SHAPE WILL BE ON THE BOARD
12
Define congruent figures using an if and only if statement without looking in your textbook.
Two geometric figures are congruent figures if and only if there is a rigid motion or a composition of rigid motions that maps one of the figures onto the other.
What is a dilation?
A transformation in which a figure is reduced or enlarged with respect to the center of dilation.
Describe the similarity transformation.
A(1,0) B(-2,-1) C(-1,-2) and R(-3,0) S(6,-3) T(3,-6)
Reflection over the y-axis and then increase in dilation.
Graph quadrilateral JKLM with vertices J(4,2) K(6,2) L(6,-2) M(3,0) and graph them after a 180 degree rotation.
Points should be J(-4,-2)
K(-6,-2)
L(-6,2)
M(-3,0)
Which transformation is the same as reflecting an object in two parallel lines? In two intersecting lines.
Transformation and Rotation
Graph triangle ABC and it's image after dilation of 2
Points: A(2,1) , B(4,1) , C(4,-1)
A'(4,2) , B'(8,2) , C'(8,-2)
What are figures that similarity transformation map them onto each other
Similar figures
The vertices of triangle are A(0,4) B(3,5) and C(2,0). Translate (x+3, y-1). Find the points
A(3,3)
B(6,4)
C(5,-1)
Describe the congruence transformation that maps triangles DEF to JKL
Graphs will be checked!!!
D(2,-1) E(4,1) F(1,2)
J(-2,-4) K(-4,-2) L(-1,-1)
THE PROBLEM IS ON THE BOARD!!!
ANSWER IS ON THE BOARD!!!
Are these figures similar? Use transformations to explain why or why not?
Graph: A(-4,1) B(-2,2) C(-2,1)
L(2,4) M(6,6) N(6,4)
Graphs will be checked
Yes they are: Translate (x,y)-(x+5, y+1)
dilate by a scale factor of 2.
Graph A(1,2) B(3,4) C(5,1) and then reflect over x=4.
Graph will be checked!!!
A'-(7,2)
B'-(5,4)
C'-(3,1)
Graph J(-1,2) l(-4,2) and (-3,4). Then graph P(1,-2) M(4,-2) N(2,-4). After find the congruence transformation.
Graphs will be checked!!!
Rotation of 180 degrees
Graph the polygon and its image after dilation with scale factor -0.5.
Points: W(8,-2) , X(6,0) , Y(-6,4) , Z(-2,2)
W'(-4,1) , X'(-3,0) , Y'(3,-2) , Z(1,-1)
Graph triangle ABC with vertices A(2,2) , G(5,4) , H(3,0) and its image after the similarity transformation.
reflection: x-axis
dilation->(2.5x,2.5y)
A'(5,-5) , B(12.5,-10) , C(7.5,0)
Graph triangle PQR with vertices P(0,-4) Q(1,3) and R(2,-5) and then graph it's image completion.
translate (x,y)-(x+1,y+2).
Graph's will be checked
P'-(1,-2)
Q'-(2,5)
R'-(3,-3)
Describe a congruency transformation that maps triangle DEF to triangle JKL
Triangle DEF: D(2,-1) , E(4,1) , F(1,2)
Triangle JKL: J(-2,-4) , K(-4,-2) , L(-1,-1)
Reflect Over the y-axis, and move up 3 units
Graph the triangle and it's dilation with scale factor k.
A(0,5) , B(-10,-5) , C(5,-5)
K=120%
A'(0,6) , B'(-12,-6) , C'(6,-6)
Define Similarity Transformation without using the textbook.
A similarity transformation is a dilation, a composition of dilations, or a composition of rigid motions and dilations.