Find the distance between the points below (9, 0) and (5,2) Find the length of the hypotenuse if...
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Transcript of Find the distance between the points below (9, 0) and (5,2) Find the length of the hypotenuse if...
Find the distance between the points below(9, 0) and (5,2)
Find the length of the hypotenuse if the length of the legs are 4 and 2
The circumference of a circle is
The distance around a circle
First we must define some things about a circle.
The radius is the distance from the center of a circle to any point on a
circle.
The diameter is the distance across a circle through the
center.
We use Pi as the measurement to help us find the circumference of a circle.
Pi, not Pie!
Two formulas are used in finding the circumference of a
circle.
Circumference = d
WHEN THE CIRCLE HAS A DIAMETER MEASUREMENT, USE THE FOLLOWING FORMULA.
4in.
Circumference = 2 r
When the radius of a circle is given, the following formula
should be used.
5 in
Tell me what formula would be used to solve the next five problems.
3in
C =
8ft
C =
122mm
C =
17.5 cm
C =
Find the perimeter of this shape
Use π = 3.14 to find perimeter of this shape.
The perimeter of this shape is made up of the circumference of a circle of diameter 13 cm and two lines of length 6 cm.
6 cm13 cm
Formula for the area of a circle
We can find the area of a circle using the formula
radius
Area of a circle = πr2
Area of a circle = π × r × r
or
The circumference of a circle
Use π = 3.14 to find the area of this circle.
A = πr24 cm
Finding the area given the diameter
The radius of a circle is half of its radius, or
We can substitute this into the formula
A = πr2
r = d2
The area of a circle
Use π = 3.14 to find the area of the following circles:
A = πr22 cm A = πr210 m
A = πr2
23 mm
A = πr278 cm
Find the area of this shape
Use π = 3.14 to find area of this shape.
The area of this shape is made up of the area of a circle of diameter 13 cm and the area of a rectangle of width 6 cm and length 13 cm.
6 cm13 cm
Holt McDougal Geometry
10-3Composite Figures
A composite figure is made up of simpleshapes, such as triangles, rectangles,trapezoids, and circles.
To find the area of a composite figure, find the areas of the simple shapes and then use the Area Addition Postulate.
Holt McDougal Geometry
10-3Composite Figures
Find the shaded area. Round to the nearest tenth, if necessary.
Example 1A: Finding the Areas of Composite Figures by Adding
Holt McDougal Geometry
10-3Composite FiguresCheck It Out! Example 1
Find the shaded area. Round to the nearest tenth, if necessary.
Holt McDougal Geometry
10-3Composite FiguresExample 2: Finding the Areas of Composite Figures by
SubtractingFind the shaded area. Round to the nearest tenth, if necessary.
Holt McDougal Geometry
10-3Composite FiguresCheck It Out! Example 2
Find the shaded area. Round to the nearest tenth, if necessary.