Similar Polygons
November 12, 2014
10/12/14
Which of these pairs of ratios (fractions) are
equal? How do you know?
1)
2)
4)
3)
5)
1
Similar Polygons
November 12, 2014
Similar Polygons
–
Two polygons are similar if and only if:
1. Corresponding angles are ___________________
2. Corresponding sides are ____________________
Ex 1:
Similar Triangles:
ABC ~
DEF
Corresponding <'s:
Corresponding Sides:
Write one proportion using pairs of corresponding
sides:
2
Similar Polygons
Defn:
November 12, 2014
– the ratio of the lengths of ________________________
of ________________________.
Note: The formula is _____________________
If
ABC is the pre-image, and
scale factor is:
DEF is the image, the
If
DEF is the pre-image, and
scale factor is:
ABC is the image, the
3
Similar Polygons
November 12, 2014
Ex 2: Similar Quadrilaterals: ABCD ~ EFGH
Corresponding <'s:
Corresponding Sides:
Write one proportion using pairs of corresponding
sides:
Scale factor if ABCD is the pre-image:
Scale factor if EFGH is the pre-image:
4
Similar Polygons
Ex 3:
November 12, 2014
JKL ~
RST.
a) Find the scale factor if
JKL is the pre-image.
b) Find the value of any missing sides and angles.
5
Similar Polygons
November 12, 2014
Ex 4: The given triangles are similar.
Find the values of x and y.
6