Circles and Circumference
What is the diameter of a circle with a radius of 8in.
16in.
Find the area of a circle with a radius of 9in.
A=(pi)(r)2
A=(3.14)(9)2
A=(3.14)(81)
A=254.34in2
Find the perimeter of the following shape.
29.7ft
Can you draw a triangle with the angle measurements of 45, 45, 90?
The angles of a triangle need to equal 180.
45+45+90=180
Yes!
What is the unknown angle of a triangle with angle measurements of 155, 10, ?
? = 15
180-155-10=15
What is the radius of a circle with a diameter of 56cm?
28cm.
Find the area of a circle with a diameter of 1.5ft.
A=(pi)(r)2
A=(3.14)(0.75)2
A=(3.14)(0.5625)
A=1.77ft2
Find the area of the following shape.
64.26 ft2
Can you draw a triangle with the angle measurements 60, 60, 80?
60+60+80=200
NO!
Find the unknown angle measurement of a triangle with angle measurements 100, 45, ?
? = 35
180-100-45=35
Find the circumference of a circle with a diameter of 8in. (Use 3.14 for pi)
C=(pi)(d)
C=(3.14)(8)
C= 25.12 in.
DOUBLE JEOPARDY
Colton
Find the area and perimeter of the following shape.
Perimeter: 29cm
Area: 49.5cm2
Can you draw a quadrilateral with the angle measurements 100, 90, 65, 105?
The angles need to equal 360
100+90+65+105=360
Yes
Find the unknown angle measurement of the quadrilateral with angle measurements of 160, 30, 20, ?
? = 150
Find the circumference of a circle with a radius of 2m. (use 22/7 for pi)
C=2(pi)(r)
C=2(22/7)(2)
C= (22/7)(4)
C= 88/7m OR 12.57m
Find the area of a semicircle with a diameter of 30in.
A=(pi)(r)2/2
A=(3.14)(15)2/2
A=(3.14)(225)/2
A=706.5/2
A=353.25in2
Find the area and perimeter of the following shape.
Perimeter: 55.1ft
Area: 236.625ft2
Use a protractor to draw a triangle with the angle measurements of 90, 55, and 35.
90+55+35=180
Triangle is possible.
Look at triangles.
Find the unknown angle measurement of a quadrilateral with angle measurements of 120, 120, ?, ?
?=60
?=60
360-120-120=120
120/2=60
What is the radius of a circle with a circumference of 122 cm.
C=2(pi)(r)
122=2(3.14)(r)
122=6.28(r)
19.43 cm=r
Which is one has a bigger radius?
A circle with a circumference of 50in or a semicircle with a circumference of 75in?
C=2(pi)(r)
50=2(3.14)(r)
r=7.96in
C=2(pi)(r)/2
75=2(3.14)(r)/2
150=6.28(r)
r=23.88in
Circle with a circumference of 75in!!
Is your friend correct? Why or why not.
No, they added the 5 twice.
Use a protractor to draw a quadrilateral with angle measurements of 45, 50, 130 135
45+50+130+135=360
Quadrilateral is possible.
DOUBLE JEOPARDY!!!!
Miles Teller