Area
Circumference
Vocabulary (Mostly)
Review: Combining Like Terms
Random
100
What is the formula for area of a circle?
Area = pir^2
100
What are both formulas for circumference of a circle?
Need BOTH
C=2pir or C=pid
100
What is another name for a perimeter of a circle?
The circumference
100
Combine:
10y+8x+7y+11x
17y+19x or 19x+17y
100
What is the black line called?
Radius
200
What is the area of this circle to the nearest tenth?
A=pir^2
A=49pi=153.9 i n^2
200
What is the circumference of this, to the nearest tenth?
C=pid=8pi=25.1cm
200
What is the red line called?
Diameter
200
Combine like terms:
11x-9y+20x+11y
31x+2y or 2y+31x
200
If the Radius is 20 ft, what is the diameter?
double, so 40 ft.
300
What is the area of this circle, to the nearest tenth?
the radius = 9 so...
A=pir^2 =9^2pi=81pi=254.5
(254.4 works)
300
What is the circumference, to the nearest tenth, from a circle with a diameter of 51 cm?
C=pid=pi51=160.2 cm
300
If the diameter is 14 cm, what is the radius?
half of it, so 7 cm.
300
Combine like terms:
48y-11x-x-10x+50y=
-22x+98y or 98y-22x
300
What is:
7-2 2/3=
4 1/3
400
What is the radius?
What is the area?
What is the diameter?
radius = 3
area =
pir^2=3^2pi=9pi=28.3 or 28.2
d=6
400
What is the circumference to the nearest tenth, of a circle with a radius of 17 cm?
C=2pir=2pi17=34pi=106.8 cm
or C=pid=pi34=106.8 cm
400
If the diameter of a circle is 18, what is the AREA of the circle? (Draw a picture if this helps)
Radius =
18div2=9
A=pir^2=pi9^2=81pi=254.5 or 254.4
400
11x - 10y+6y-100x
-89x-4y
400
Find area:
24 + 12 = 36
500
What is the area in terms of pi?
RADIUS = 6 SO....
A=pir^2=6^2pi=36pi
500
What is the circumference in terms of pi?
DIAMETER = 16 SO... OR
2pir=2pi8=16pi
500
The gardener needs to find the area of this circular garden, what is the area to the nearest tenth?
A=pir^2
radius = 21 div 2 = 10.5
A=pi10.5^2=110.25pi=346.4 or 346.3
500
y-x-x-x-20x-30y+10y=
-19y-23x or -23x-19y
500
Find the perimeter
26 cm