Recent questions tagged geometry

Description : Have you ever noticed that the coordinates for row and column are in the reverse order of x and y coordinates?

Last Answer : That my friend is off the charts. I always followed the cartesian coordinate system invented by René Descartes.

Description : What's the procedure for calculating the number of pieces of the edge of a puzzle of 108 total pieces?

Last Answer : Impossible, It would almost completely depends on the size of the pieces, which you don't have. Imagine this is a rectangle. You could have two large pieces on each side, making a total of 8 ... still correct. There is not enough information in the question to be able to make an educated estimate.

Description : Can you visualize this slightly more difficult 3D rotation?

Last Answer : I see it ending up in the same space. As to the location of the bottom triangle, imagine that the bottom edge is facing you frontally, and the ascending edge behind it, looking like it intersects ... while the bottom triangle will move to be in the same place as you saw the triangle facing you.

Description : Can you visualize this simple rotation in 3 dimensions?

Last Answer : If your view is frontal, I would imagine the bottom plane is now in the bottom right quadrant, the top plane in the upper left.

Description : How many kinds of circles are there, and what are they?

Last Answer : Kinds of circles? You mean tires & donuts? What of question is this and what is it?

Description : At the North Pole, are east and west just a horizontal circle around the pole?

Last Answer : That is correct, at latitude 89 degrees, 59 minutes, 59 seconds, facing north, west is to your left and east is to your right. And each step left or right crosses many degrees of longitude. You cross a lot of time zones as you walk a small circle.

Description : What is the square of a triangle?

Last Answer : The only way to answer the verbal form is by carefully being sure of the meanings of each word. I used to be very strong in math, but I'm rusty. When I hear square I think of a 2D ... approach, as opposed to the usual one based on concise verbal definitions, which seems to be the weak point.

Description : What is the math from turning a circle into a sphere and beyond ?

Last Answer : Although hypercube can refer to a four dimensional cube, the term also refers to any n dimensional cube. The proper term for 4 dimensional cube is teseract. Hypersphere also refers to spheres in more ... found this picture of a hypersphere, which I think does a pretty good job of representing it.

Description : Math experts: What is the relationship between adding constant increments of pancake batter and the radius of the pancake?

Last Answer : answer:The relationship is volume of pancake batter to surface area of pancake in pan. The assumption is that the batter always spreads out at a consistent rate to a set thickness. so if a ¼ cup results in pi*r^2 size ... then ½ cup results in 2 (pi*r^2); ¾ cup batter equals 3(pi*r^2) size pancake.

Description : Do you believe in angles?

Last Answer : answer:That’s like asking whether I believe in air. Geometry comes in handy when you want to hang bookshelves straight.

Description : Besides a circle, is there any other shape that can rotate within a triangle?

Last Answer : Some sort of hexagonal shape with enough sides would, but aside from that I don’t think so. However some sides would loose contact, so if that is a requirement I would say no, there is nothing aside from a circle.

Description : Can someone help me with this geometry problem?

Last Answer : answer:Let's designate as x the angle at the top of the right triangle and for convenience designate arctan(21/93) as k. Using θ on the bottom and the exterior angle relationship gives: θ = 90 + x On the top we get θ - k + x ... to x = k/2 θ = 90 + x = 90 + k/2 = 90 + ½ arctan(21/93) = 96.36

Description : What is difference between Archimedian spiral and involute of a circle?

Last Answer : answer:From Wolfram MathWorld article on Circle Involute Pedal Curve: The pedal curve of circle involute f = cos t + t sin t g = sin t - t cos t with the center as the pedal point is the ... . The two curves are compared in this image from Wikipedia (black = circle involute; red = A. spiral).

Description : If you know the values of a function at the three points of a triangle, how can I determine the values at points in the interior? {details}?

Last Answer : Noticing the fact that on the first two triangles in the image that points of equal values lay on parallel lines, I wonder if this is the case for the larger triangle. If it is, then the parallel ... not parallel to the sides of the triangle, and I wonder how to find the equations for the lines.

Description : Smallest circle that intersects N number of points on the coordinate plane?

Last Answer : I don’t see how the upper bound is radius of 20. How does that circle have “20 intersection points?”

Description : Is there a 3 dimensional shape that has 6 equal angles?

Last Answer : An octahedron has 6 vertices. It is a platonic solid with 8 faces, each an equilateral triangle, & 12 edges. Image

Description : Do you think my professor just screwed up when writing this calculus problem, or am I overlooking something?

Last Answer : answer:Yeah, your professor screwed up. The graphs do not intersect. Man, I had not made graphs in a long time.

Description : How do I edit a Wikipedia article?

Last Answer : Go to the discussion page, click the edit button and follow the guidelines.

Description : Why do they call it "past 97 degrees" on the Hershey rollercoaster?

Last Answer : If it’s a 97 degree angle, then yes, it’s not quite vertical. I don’t think an 83 degree drop is possible, is it?

Description : How to visualize four dimensions?

Last Answer : answer:Use an interactive model, for instance a three-dimensional image and add a slider to “move” through the fourth dimension. In essence any movieclip is a four-dimensional model, be it linear and limited in its interactivity.

Description : What's the formula for these special right triangles?

Last Answer : answer:In a 45-45-90 triangle, the measure of the hypotenuse is equal to the measure of a leg multiplied by SQRT(2). In a 30-60-90 triangle, the measure of the hypotenuse is two times that of the ... 30o angle. The measure of the other leg is SQRT(3) times that of the leg opposite the 30o angle.

Description : What is the grade/slope/angle?

Last Answer : answer:AFAIK, civil engineers try to accommodate both the terrain and the tolerances on cars. Calculating the slope is just plain geometry (we know that the road rises a total of about 15 feet, but we ... is more to grading than just geometry, since one must also figure in the speed of the vehicle.

Description : Can you help me with proofs?

Last Answer : Are you able to do stuff without the two column style? By that, I mean are you able to “see” why whatever you are trying to prove is true? Could you explain it in and pictures, etc…?

Description : How to visualize four dimensions?

Last Answer : answer:Use an interactive model, for instance a three-dimensional image and add a slider to “move” through the fourth dimension. In essence any movieclip is a four-dimensional model, be it linear and limited in its interactivity.

Description : What is the value of .03 x .50?

Last Answer : Try converting everything to exponential notation or think “what is half of .03?”.

Description : A^2 + b^2 = c^2 What does it prove?

Last Answer : That two things equal another.

Description : Another Geometry question (easy one this time.) Can you help me?

Last Answer : All the pictures I have seen of graphing quadrants, have labeled the 4 areas in a counterclockwise way. Top right is I & bottom right is IV. Even after doing a quick google search just ... quadrants in this way. Because math is an exact science, quadrant labeling isn't about personal preference.

Description : Geometry help please?

Last Answer : Protip: regular N-gons can be divided into identical triangles, trapezoids and parallelograms can all be split in triangles and rectangles. Calculate their areas independently and add them at the end.

Description : What is the natural history of the straight edge?

Last Answer : Various forms of razors were used throughout history, which are different in appearance but similar in use to modern straight razors. In prehistoric times clam shells, shark's teeth, and flint were sharpened ... a century later.[6]...there's much more http://en.wikipedia.org/wiki/Straight_razor

Description : If triangle geometry is called trigonometry, what is circle geometry called?

Last Answer : My best guess would be polar, but that more refers to how to graph something with respect to circular coordinates than the actual geometric properties of a circle. Hmm, this is a tough one!

Description : Is there a specific name for this sort of decorative line pattern?

Last Answer : sorry i have no clue

Description : What is an enneagram?

Last Answer : answer:You mean this? http://en.wikipedia.org/wiki/Enneagram_of_Personality

Description : What is SIN, TAN, COS?

Last Answer : Wikipedia knows.

Description : With sketch, justify use of Variable Geometry Turbocharger as compared to fixed geometry turbocharger. 

Last Answer : Variable Turbine Geometry technology is the next generation in turbocharger technology where the turbo uses variable vanes to control exhaust flow against the turbine blades. The problem with the ... The angles of the vanes vary throughout the engine RPM range to optimize turbine behaviour.

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