Which is the area of a circle with circumference of 15.7 units?( Use 3.14 for )

2 answers:

7 0

Circumference of a circle= 2πr = 15.7
from this radius r= 15.7/ 2π
r= 15.7/(2x 3.14)
r= 15.7/ 6.28 = 2.5
therefore area = π r^2= π x r x r
= 3.14 x 2.5 X 2.5 = 19.625 sq units

damaskus [11]2 years ago

4 0

A = π(r²) --- r is radius

C = πd --- d is diameter

First, the circumference must be found. If the circumference is 15.7, plug it in.

15.7 = πd

We know what pi is.

15.7 = 3.14 (d)

Now, simply divide 3.14 by 15.7 to find the diameter (d). You get 5. Since the radius is half of the diameter, the radius is 2.5. Plug this into the area formula, and plug pi in, too.

A = 3.14(2.5²)

2.5 to the second power is 6.25.

A = 3.14(6.25)

Tada! Multiply, and you're left with 19.625!

You might be interested in

Jordans have a rectangular garden. want to build a diagonal pathway across he garden. the length of pathway is 90 ft. width of g

blondinia [14]

So we see the pythagorean theorem
a^2+b^2=c^2
diagonal=c
width=a or b, pick one
width=a
legnth=b
width is 5 times more than 2 times legnth of garden
w=5(2legnth)
this doesn't make sense since the legnth is normally longer than the width, but we'll stick with that
w=5(2l)
w=10l
a=10b
(10b)^2+b^2=90^2
100b^2+b^2=8100
101b^2=8100
divide by 101
b^2=80.198 aprox 80.2
square root
8.95533
legnth of garden =8.96
to find width subsitue
w=10l
w=89.56

legnth=8.96
width=89.56

4 0

2 years ago

Read 2 more answers

L(t) models the length of each day (in minutes) in Manila, Philippines tt days after the spring equinox. Here, t is entered in r

SVETLANKA909090 [29]

Answer:

Given that:

$L(t) = 52\sin(\frac{2 \pi t}{365})+728$