polygon yes no 1/l1.7/slides.pdf · 2017-03-07 · 3 polygon a closed geometric figure formed by...
TRANSCRIPT
1
Warmup:
2
Use inductive reasoning to form a conjecture about the following 2 sets of figures:
Yes No
3
Polygon
A closed geometric figure formed by connecting line segments endpt to endpt,
each seg intersecting exactly 2 others.
Yes No
What do you have, if in a plane
you take a pt and
all other points equidistant from that pt?
4
Circle
Set of all pts in a plane equidistant from a given point.
Perimeter
Sum of the len of each side.
Perim P of a square w/side len s:
P = 4s
Perim P of a rectangle w/base b, height h:
P = 2b + 2h
5
Margaret's garden is a square 12ft on each side.She wants a 1ft wide path around the entire garden.What will the outside perimeter of the path be?
1
What do we call "perimeter" for circles?
6
Circumference
"Perimeter" for a circle.
Circumference C of a circle of diameter d is:
C = πd = 2πr
Questions
Next
7
1
OG has a radius of 6.5cm. Find the circumference of OG in terms of π:
2
2)
3)
πcircumference of OG =
Now find the circumference of OG to the nearest tenth.
back
8
Area
Measure of how much surface space a shape takes up.
Area A of a square w/side len s:
A = s2
Area A of a rectange w/base b and height h:
A = bh
Area A of a circle of diameter d is:
A = πr2
9
To make a project, you need a rectangular piece of fabric 36" wide & 4' long.How many square feet of fabric do you need?
1
area of OB = .... π.2
1.5 yd
10
Postulate 19
Two figures are congruent if their areas are equal.
What is the area of this polygon?
2'
1'
2'
1'
2'
1'
2'
1'
2'
1'
2
11
Postulate 110
The area of a region is the sum of the areas of nonoverlapping parts.
1'
4'
4'2'
3'
3'
Find the area of the white region. All ...'s are rt ...'s. Not drawn to scale.
3
12
Pg 55, #141 odd, 50, 5457, 61, 68, 69, 72
L1.7 HW Problems