Explore BrainMass
Share

# Circles

### Diameter - Two cars with new tires are driven at an average speed of 60 mph...

Two cars with new tires are driven at an average speed of 60 mph for a test drive of 2000 miles. The diameter of the wheels of one car is 15 inches. The diameter of the wheels of the other car is 16 inches. If the tires are equally durable and differ only by diameter, which car will probably need new tires first?

### Given a circle, construct a circle with twice its area.

Given a circle, construct a circle with twice its area. I know that the r2 = (x-h)2 + (y+k)2 is the standard equation for a circle. I don't know how to use this formula to construct two circles where one is twice the area of the other.

### Find the Equation of a Circle

Find an equation of the circle which touches the straight-lines x + y = 2 and x - y = 2 and touches the circle x2 + y2 =1?

### Revolutions of a tire

Two cars with new tires are driven at an average speed of 60 mph for a test drive of 2000 miles. The diameter of the wheels of one car is 15 inches. The diameter of the wheels of the other car is 16 inches. How many revolutions does each tire make?

### Infinite Series of Circles inside Squares & Equilateral Triangle

A circle of radius 100is inscribed in a square. The inscribing process continues to infinity. What is the sum of the unshaded areas? Radius of 1 = 100 - Radius of 2 = _________Radius of 3 = _______ Radius of 4 = ____________ Side of square 1 =________, Side of square 2 = __________, Side of square 3 = ___________Side of

### Two circles, A and B, touch each other at exactly one point...

Two circles, A and B, touch each other at exactly one point, as shown in the diagram below. The equation of circle A is . Circle B has centre (1, k + 1) and radius 4. Please see the attached file for the fully formatted problems. (Not to scale) a) i) Find the completed square form of x2 - 18x Find the completed sq

### Effect on Volume of Sphere when Radius and Surface Area are Changed

If the radius of a sphere is increased by 20% then the surface area is increased by 44%. By what percent exactly is the volume increased?

### Center and radius of sphere

Find the center and radius of the sphere x^2 + 8x + y^2 - 14y + z^2 - 8z = -56

### Evaluate Complex Variable (Contour; Circular Arc)

See attachment for better symbol representation: 11. Evaluate integral r (2z + 1) dz where R is the following contour from z = -i to z= i. c. the circular arc z = e^it for -pi/2 < t < 0

### Tangency of three circles Tangency of 3rd circle to other circles

Tangency of three circles B elow is how I created the sketch shown in the other attachment: 1. Create two tangent circles with centers A and B. For convenience sake, let circle A hav

### How to Find Center and Radius of Circles

(a) Consider the circle: (x+2)squared + (y-1)squared =9. Find the center and radius of the circle. (b) Consider the circles: x squared + y squared + 4x-4y-1=0 x squared + y squared -2x+4y-4=0 (i) Find the center of each circle. (ii) Find the distance between the centers if the circles are plotted on the same rectangu

### Find the pipe radius in terms of the block height

A pipe is supported by a block and a wall.Find the pipe radius in terms of the block height and its distance from the wall. A block with height "b" is placed a distance "a" from a wall, to hold in place a pipe with radius "R" (the pipe is supported by the wall on the other side - see attached figure). Find the radius "R" in ter

### Finding the Area of a Circle using the Unit Circle

Please see the attached file for the fully formatted problems. Given square is 11*11, unit square is 1*1 without using any algebraic equation by using scissors or folding it, we can find the area of 11*11 square in terms of unit square. With a similar idea we can do triangles (Main triangle and unit triangle).

### Finding the area between two circles inner-tangential to a parabola.

Imagine a valley y=x^2. A circle with radius = 5 is inside it. Another circle, with radius = 4 is above the previous circle, (and inclined to right side) (PLEASE SEE THE ATTACHMENT zip file) Find the area between y=x^2 and the 2 circles (Not allowed to use computer.)

### Tangent Circles

Please see the attached file for the fully formatted problems. Two congruent semicircles lie on the diameter of a third semicircle, each tangent to the other two. A small circle is tangent to all three semicircles. If the area of the shaded region is 45pi, what is the length of the radius of the small circle.

### Circumference and area of a circle

Need to know the formula for finding area and circumference of a circle 2

### Finding the area of the segment bound by an arc in a circle.

In a circle of radius 6 centimeters, find the area of the segment bound by an arc of measure 120 degrees and the chord joining the endpoints of the arc. Round your answer to nearest tenth. A. 36.1 cm squared B. 6.8 cm squared C. 5.7 cm squared D. none of these