Questions on Geometry: Circles and their properties answered by real tutors!

Tutors Answer Your Questions about Circles (FREE)

Question 426383: how do i solve this problem??
"if a circle has an area of 81 pi inches squared what is the circumference. leave your answer in terms of pi."
Click here to see answer by ikleyn(53364)

Question 1165093: A seismological station is located at (0 ,3), 3 km away from a straight shoreline
where the x-axis runs through. The epicenter of an earthquake was determined to
be 6 km away from the station.
(a) Find the equation of the curve that contains the possible location of the
epicenter.
(b) If furthermore, the epicenter was determined to be 2 km away from the shore,
find its possible coordinates (rounded off to two decimal places).

Click here to see answer by MathLover1(20854)

Question 571232: A park has just installed a circular fountain in 8 meters diameter. The park wants to pave a 1.5 meter wide path around the fountain. If paving costs 10 dollars per square meter, find the cost to the nearest dollar of the paved path around the fountain.
Click here to see answer by ikleyn(53364)

Question 540930: If we have 2 circles that intersect... each one attaching to the midpoint of the other circle, how do we explain using information about circle, why you know that the sides are all the same length.(Which would be a triangle drawn in the intersection between both circles) Please help me... Thank you :)
Click here to see answer by ikleyn(53364)

Question 563793: The larger circle circumscribes an equilateral triangle, which circumscribes a small circle. The area of the larger circle is 12pi. What is the triangle's perimeter. I not sure how to do this problem and how to work it out.
Click here to see answer by ikleyn(53364)

Question 1202895: 15. The original "Ferris" wheel, designed by George Washington Gale Ferris Jr., was built for the World's Columbian Exposition of 1893 in Chicago, Illinois. There were 36 fully enclosed gondolas (passenger cars) that carried up to 40 passengers.
This "Ferris" wheel eventually left Chicago and was relocated in St. Louis, Missouri in time for the 1904 Louisiana Purchase Exposition. On May 11, 1906, it was demolished using a dynamite charge and sold for scraps.
The circumference of the "Ferris" wheel had to be large enough to allow for an arc length of 20.64 ft between each gondola. What was the circumference of the original "Ferris" wheel? Round to the nearest whole number.
Click here to see answer by Edwin McCravy(20077)

Question 1210387: A television tower broadcasts its signal at a range of 18.1 miles from the tower to its further point. How many square miles are covered by the range of this tower? Round your answer to the nearest hundredth if necessary.
Click here to see answer by ikleyn(53364)

Question 1167805: The figure below shows two pulleys of radii 6cm and 4cm with centres A and B respectively. AB = 8cm. The pulleys are connected by a string PQXRSY
https://www.easyelimu.com/images/topicalrevision/maths/form_3/circles_chords_and_tangents/circle_q5.PNG
calculate
(a) Length PQ
(b) PAS reflex
(c) Length of arc PYS and QXR
(d) The total length of the string PQXRSY
Click here to see answer by ikleyn(53364)

Question 1176479: Given seven equal circles on a hexagonal grid, how many permutations are possible where circles are always adjacent (repetitions such as inversions and reflections excluded)?
Thank you.
Click here to see answer by ikleyn(53364)

Question 1177001: EVOL is a cyclic quadrilateral, inscribed in a circle with center S. Given that the radius of this circle is 25 in. and angle VEL is 55 degrees, explain your work to find the following measurements.
a)Length of Major Arc VL
b)Angle measure of Minor Arc VL
c)Angle VOL
d)Length of Chord VL
Click here to see answer by ikleyn(53364)

Question 1209532: Point R is chosen on the circumference of a circle and arc PQ is drawn with R as its center. If P and Q are joined, the line segment formed is a diameter of the circle with length 2r cm. Find the area of the shaded region in terms of r, in square centimeters.
Link to diagram: https://ibb.co/GQFdy2SV
Click here to see answer by ikleyn(53364)

Question 1209524: (46) Sector ABC is 1/12 of a circle with diameter 24k. Line segment AD is perpendicular to segment BC. Find the area of the shaded region.
Link to diagram: https://ibb.co/5gNwX0K6
Click here to see answer by ikleyn(53364)

Question 1210278: How to solve slant height of a cone
Click here to see answer by MathLover1(20854)

Question 1168234: Find the general equation of the circle, if the circle is tangent to the line -3x+2y+1=0 at the point (1, 1), and the center is on the line x+y-1=0.
Click here to see answer by MathLover1(20854)

Question 1168232: A circle is centered at (2,1) and tangent to the line x+y=0.
(a) find the equation of the circle
(b) find the area and circumference of the circle.
Click here to see answer by MathLover1(20854)

Question 1168231: Find the equation of a circle is tangent to the line -x+y+4=0 at the point (3, -1), and the center is on (1, 1).
Click here to see answer by MathLover1(20854)

Question 1209844:
Click here to see answer by ikleyn(53364)

Question 1209844:
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Question 1209799: 1. 137+6y=-y^2-x^2-24x
2. x^2+y^2+14x-12y+4=0
3. y^2+2x+x^2=24y-120
4. x^2+2x+y^2=55+10y
5. 8x+32y+y^2=-263-x^2
Click here to see answer by CPhill(2138)

Question 1209799: 1. 137+6y=-y^2-x^2-24x
2. x^2+y^2+14x-12y+4=0
3. y^2+2x+x^2=24y-120
4. x^2+2x+y^2=55+10y
5. 8x+32y+y^2=-263-x^2
Click here to see answer by timofer(134)

Question 1209798: 137+6y=-y^2-x^2-24x

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Question 1209798: 137+6y=-y^2-x^2-24x

Click here to see answer by josgarithmetic(39684)

Question 1209526: (55) Equilateral triangle ABC, with a side of length 4, is inscribed in a circle. The midpoint of AB is D and the midpoint of AC is E. If DE is extended to meet the circle at F, find the length of EF.
Link to diagram: https://ibb.co/6czn24rm
Click here to see answer by ikleyn(53364)

Question 1209525: (49) In the diagram, ABCD is a unit square. Arc AC has center D and arc BD has center C. Find the shaded area in square units.
Link to diagram: https://ibb.co/zhCbbmhz
Click here to see answer by ikleyn(53364)

Question 1209521: (42) Two circles of unit radius with centers A and B are tangent to each other at C. They are also tangent internally to a circle with center C. Find the area of the shaded region.
Link to diagram: https://ibb.co/QFchDRT5
Click here to see answer by ikleyn(53364)

Question 1209274: A tractor has a rear wheel with a circumference of x m. The circumference of the front wheel is 5 m less. If the front wheel makes 15 more revolutions than the rear wheel every 450 m, what is the circumference, in m, of the front wheel?

Click here to see answer by math_tutor2020(3827)

Question 1208994: An archery target is constructed of five concentric circles such that the area of the inner circle is equal to the area of each of the four rings. If the radius of the outer circle is 12 m, then the width of band a, in m.
https://ibb.co/h78NMWQ
I am very confused as to which band is a and what method to use for this
Click here to see answer by ikleyn(53364)

Question 1208982: Two concentric circles are drawn so that the shaded area is equal to the unshaded area. The radius of the outer circle is 8 cm. Find the difference in the radii of the two circles.

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Question 1208635: Find the equation of a circle inscribed in a triangle with the sides on the lines x-3y=-5, 3x+y=1 and 3x-y=-11.
Click here to see answer by math_tutor2020(3827)

Question 1208635: Find the equation of a circle inscribed in a triangle with the sides on the lines x-3y=-5, 3x+y=1 and 3x-y=-11.
Click here to see answer by ikleyn(53364)

Question 1208635: Find the equation of a circle inscribed in a triangle with the sides on the lines x-3y=-5, 3x+y=1 and 3x-y=-11.
Click here to see answer by Feliz_1965(1)

Question 1208636: “Find the equation of a circle inscribed in a triangle with the sides on the lines x-3y=-5, 3x+y=1 and 3x-y=-11.”
Click here to see answer by math_tutor2020(3827)

Question 1208636: “Find the equation of a circle inscribed in a triangle with the sides on the lines x-3y=-5, 3x+y=1 and 3x-y=-11.”
Click here to see answer by greenestamps(13250)

Question 1208632: find the equation of the circle inscribed in a triangle with the sides on the lines x-3y=-5, 3x+y=1 and 3x-y=-11
Click here to see answer by math_tutor2020(3827)

Question 1207930: The general form of an equation of a circle is given. Convert to the standard form.

2x^2 + 2y^2 + 8x + 7 = 0

Let me see.

2x^2 + 8x + 2y^2 = (-7)^2

2(x^2 + 4x) + y^2 = 49

2(x^2 + 4x + 4) + y^2 = 49

2(x + 2)(x + 2) + y^2 = 49

2(x + 2)^2 + y^2 = 49

Is this right?

Click here to see answer by MathTherapy(10581)

Question 1207942: Write the standard form of the equation of the circle and the general form of the equation of the circle with radius r and center (h,k). Graph the circle.

r = 1/2; (h,k) = (0, -1/2)

Note: Circle is not centered at the origin.
Click here to see answer by Edwin McCravy(20077)

Question 1207943: A. Find the center and radius of the circle.

B. Graph the circle.

C. Find the intercepts of the circle, if any.

3x^2 + 3y^2 - 12y = 0

Click here to see answer by Alan3354(69443)

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