# Circles Homework 15 840

Smartandfun - Thanks for your question. I think I can help both you and your daughter. First, let's talk about Area. The Area of anything (circle, square, triangle, etc.) is always in terms of units squared. For example, a square where each side is 2inches has a perimeter (distance around) of 8inches and an area of 4inches squared. It's squared because we multiplied 2inches X 2 inches which = 4inches squared.

In example #4 the "m" simply represents the units (i.e. meters). It is "m squared" since the 78.5 represents the Area of the circle, and Area is always units squared.

I don't know the type of measurement (units) for your daughter's specific math problem, but whatever it is,those units would also squared.

But let's not get hung up on the units. What we know is that the Area of the circle is 200.96 and we want to figure out the circumference. If you look at the equations for the Area of a circle and the Circumference of a circle, they both have r (radius) in them. So if we could figure out the radius of the circle knowing the Area, then we could plug the radius of the circle into the Circumference equation in order to find the circumference.

So let's do that. We will let ?=3.14 to solve the problem:

step 1: A=2(?)r ^squared

step 2: 200.96 = ?r ^squared

step 3: 64=r ^squared (divide both sides of equation by 3.14)

step 4: 8=r (take the square root of both sides of the equation)

Now that we know the radius of the circle is 8 units we can substitute 8 for r into the circumference equation as follows:

C=2?r

C= 2?8 (we know r = 8 so plug it into the equation)

C=16? (multiple 2 X 8 to get 16)

C=16(3.14) (let ? = 3.14 to solve)

C=50.24units

Therefore, a circle with an Area of 200.96 units^squared has a radius of 8 units and a Circumference of 50.24 units.

I hope this helps. Thanks for asking.

**No answers ... yet!**

I really am lost and need help!

Circle 1: center (8, 5) and radius 6 Circle 2: center (−2, 1) and radius 2 What transformations can be applied to Circle 1 to prove that the circles are similar? What scale factor does...

4 hours ago | Katie from Mount Vernon, OH | 0 Answers | 0 Votes

Circles**No answers ... yet!**

How do you do this word problem?

Two circles have radii 6 cm and their centers are 6 cm apart. Find the area of the region common to both circles.

Mar 7 | Nick from Latrobe, PA | 0 Answers | 1 Vote

GeometryArea Of Sector And Arc LengthGeometry Word ProblemsCircles**No answers ... yet!**

Central Angles

The diameter of a circle is 120 meters. The circumference of the circle is 377 meters and the area is 11,309 m^2. Find the measure of a central angle in degrees and in radians.

Feb 26 | Delilah from Clermont, FL | 0 Answers | 0 Votes

GeometryCirclesGeometry Honors### Mark M.

Carson, CA

Measure of a central angle

A Ferris wheel has a diameter of 120 meters, a circumference of 377 meters and an area of 11,309 m^2. There are 30 cars equally spread around the Ferris wheel for people to sit or stand. Find the...

GeometryWord ProblemCircles### Arturo O.

Melbourne, FL

Circumference Using Diameter

What is the circumference of a circle, if the diameter is 120 m? What is the area? ( I am checking my answers from my homework to ensure that I got this one correct! :-) )&nb...

GeometryCirclesCircumference And Area Of CircleCircumference Math Equation### Kenneth S.

Mesa, AZ

If two circles intersect at two points, prove that their centres lie on the perpendicular bisector of the common chord.

This is question from NCERT book class 9. I want the solution before 18 hours. Because next day I have exam.

Feb 17 | Aaditya from Arvada, CO | 1 Answer | 0 Votes

Circles### Scott S.

Frederick, MD

Help pls! Thank you

Find the radius of the circle which circumscribes a square of side 10cm.

Feb 16 | Cheyenne from Schenectady, NY | 2 Answers | -1 Votes

RadiusCircles### Mark M.

Carson, CA

a circle has the equation x^2+y^2=50. Find the equation of the tangents to the circle that are parallel to x+y=8

I managed to do all the questions apart from this one, and have no idea how to even start it

Jan 21 | Amelie from New York, NY | 1 Answer | 0 Votes

GraphsCirclesCircle EquationsCircle GraphTangent Of Circle**No answers ... yet!**

In figure AB =AD=DC=PB and angle DBC =20. determine angle ABD AND APB.

In figure AB =AD=DC=PB and angle DBC =20. determine angle ABD AND APB.hence prove that Ap is parallel to Db. Please answer the questions

Jan 28 | Sushant from New York, NY | 0 Answers | 0 Votes

Circles**No answers ... yet!**

If r and R are the radii of smallest and largest circles which passes through (5, 6) and touches the circle (x-2)^2+y^2=4 , then value of r*R=p/q is then p+q is

The answer is 45.Please send the complete solution.

Dec 21 | Akarsh from Floral Park, NY | 0 Answers | 1 Vote

Circles### Kenneth S.

Mesa, AZ

May I ask about Tau and Pi ?

Teacher, I ever heard that Tau was the one true circle constant. Then 2Pi? Aren't they same ?

Dec 17 | Top from New York, NY | 1 Answer | 0 Votes

Circles### Mark M.

Carson, CA

Find the degree measure of the arc of a sector

Find the degree measure of the arc of a sector whose area is 18π square units given that the length of the radius is 12 units

Dec 14 | Erik from New York, NY | 1 Answer | 0 Votes

Area Of A SectorGeometryCircles### Andrew M.

Palm Bay, FL

The graph on the right shows a circle with its center. There are 40 stone blocks situated uniformly on the circle. The diameter of the circle is 27 meters.

a. What is the radius of the circle? b. What is the circumference? c. Since there are 40 stones located on the circumference, how far apart are the centers of the stones? The stones are all...

Dec 14 | Megan from Corona, CA | 1 Answer | 0 Votes

Circles### Kenneth S.

Mesa, AZ

If r and R are the radii of smallest and largest circles which passes through (5, 6) and touches the circle , then value of r*R=p/q is then p+q is _________?

The answer is 45.Please send the complete solution.

Dec 21 | Akarsh from Floral Park, NY | 1 Answer | -1 Votes

Circles### Don L.

Jacksonville, FL

what are the coordinates of the center and the length of the radius of the circle?

The equation of a circle is x^2+y^2-2x+6y+3=0. What are the coordinates of the center and the length of the radius of the circle.

RadiusCircleCirclesHelp Asap PleaseGeometry### Richard P.

Alexandria, VA

Find the standard form of the equation for the circle with the following properties. Endpoints of a diameter are (8,10) and (2,12)

help asap

Nov 5 | Anna from Smithville, TN | 1 Answer | 0 Votes

Circles**No answers ... yet!**

Circle and square distance relationship

I'm sure there is a formula... here is my reference http://conepatterns.com/Intersection.jpg I want to know how derive the answer for the distance from the center of the...

Nov 14 | Sean from Greenbrier, TN | 0 Answers | 0 Votes

Circles**No answers ... yet!**

Formula for circles and squares?

I'm sure there is a formula... here is my reference http://conepatterns.com/Intersection.jpg I want to know how derive the answer for the distance from the center of the...

Nov 14 | Sean from Greenbrier, TN | 0 Answers | 0 Votes

Circles### Mark M.

Carson, CA

Two concentric circles of radius 12cm and 13cm are drawn. The chord of the larger circle is tangent to the smaller circle. Find the length of the chord.

Draw an appropriate figure

Oct 2 | Gool from Sadieville, KY | 1 Answer | 0 Votes

CirclesGeometry### Arthur D.

Saugus, MA

Finding shaded area of circle

How do I find the area of the shaded area if the circle's radii are 15cm and 13cm and the angle of the triangle in it is 80? What formulas do I have to use? http://i...

7/24/2016 | Kyle from Beverly Hills, CA | 1 Answer | 0 Votes

Circles
## 0 Thoughts to “Circles Homework 15 840”