# shapes

1. ### I'm a 7th grader and I have a bad knowledge of shapes. Help?

So, for all my life, I always sucked at shape, I always forget the formula, I don't understand Pi, I tend to forget a lot of the definition for some words, scale factor is probably the most confusing thing for me, and 3D shapes are very hard for me. I find pre algebra a lot easier than even...
2. ### How to compare two vectors with their shapes and values? Using Matlab

Hi! I want to correlate two vectors not only in their shape but also considering their values in matlab. The functions i've searched (like, corrcoef/corr/corr2...) give the R-value, but that just consider the shape of the curve that the vectors represent, and i want to know also how close their...
3. ### Poincaré Disc Model - what is it, exactly? What projected shapes do, and don't, count

I am trying to get a handle on what is and is not the PoincarĂ© disc model. I think I see over on wiki that it's the projection of a given wibbly shape, through a disc to a point. As in this image, shamelessly linked from aforementioned Wiki: So there's my disc, in grey, at the bottom, and on...
4. ### Statistics data distribution shapes

Hey, for the graph in is it (1) cosidered normall distribution with the data fairly symetrical about the median wheras (2) is skewed to the right, also with data fairly symetrical about the median? Cheers
5. ### Optimization for shapes?

The problem is posted here: Gutter : nrich.maths.org I tried subbing in values to get the biggest area:perimeter ratio possible. I used an arbitrary value, 12, for perimeter. For the triangle, I took out the hypotenuse and so A = 1/2(x)(y) where x+ y = 12. Its area is biggest when x = y = 6 so...
6. ### volume AND ration - similar shapes

Hi, I was stuck on a question and was wondering if anyone could help me. A cone is split into two pieces of equal volume. Show that the large cone is about 26% taller than the small cone Hint: begin by finding the volume scale factor for the two cones Thanks
7. ### Derivative of Areas of Shapes related to their perimter

I'm stumped with a question my boss posed to me today. He explained how since the area of a circle is Pi * r^2, its derivative is 2Pi * r, the same as it's circumference (due to the infinitesimal change in area equaling the circumference). Now, take a square. It's area is x^2 derivative = 2x...
8. ### finding lengths and other from algebraic equations of shapes

a few questions question 2 rectangular shape area of land is represented by: 2x^2 + 17xy +21y^2 give the possible expressions that represent the dimmensions, and a fence will be planted around the shape, and it will be x meters from the pitch. Give the algebreic expression that reprsents the...
9. ### Plotting specific shapes for graphs.

I'm interested in what shapes you can plot on a graph (cartesian co-ordinates) using an equation (1 line) like y=x...... I'm want to know if you can plot a cycloid on a graph with an equation....
10. ### Need help with the optimization of volume of 3 dimensional shapes.

A right circular cylinder is inscribed in a cone with height H and base radius R. Find the largest volume of such a cylinder (you should assume they are rotated about the same axis). If you could please solve in a step by step manner and explain each step, I would greatly appreciate it. Thank you.
11. ### Two shapes and one line.

The furthest I've gotten is 60 = 4x + 3y PS, this is just for a test I'm taking online, I'm not even in a calculus class. Don't think I'm trying to cheat or anything.
12. ### TI-nspire CX calculator - how to create basic geometry shapes on the scratchpad

I recently bought a TI-nspire CX calculator. I've found all kinds of useful help on how to manipulate geometric shapes in a graphing document or the scratchpad. However, I haven't had any success in learning how to create or graph basic shapes myself. I'd appreciate help on how to plot a...

Chuck used a dynamic geometry utility and kept drawing bow tie shapes. To do this, he used two parallel lines where A, and B are on one line, C and D are on the other. He moved only point D to change the shape. Elizabeth noted that no matter where he moved D, one thing remained true about the...
14. ### Creation of a General Formula for a family of Curve Shapes

I have a process that requires an operational profile that follows one of the curves in the diagram which follows. I wish to program into the device a general equation that will give me a family of curves of this general shape. The goal is to adjust the parameters of the equation so that I can...
15. ### Creation of a General Formula for a family of Curve Shapes

I have a process that requires an operational profile that follows one of the curves in the diagram which follows. I wish to program into the device a general equation that will give me a family of curves of this general shape. The goal is to adjust the parameters of the equation so that I can...
16. ### Difficult - Galaxy Shapes

Hi MHF, I'm a physics undergraduate student at Oxford doing his MPhys project. I've got a problem that to me seems quite difficult but may be very easy for an experienced statistician. I'll lay out the problem below. Is there anyone in the department who could give me a clue as to if I'm on the...
17. ### Volume between two shapes (one inscribed in the other)

Problem: If a square prism is inscribed in a right circular cylinder of radius 3 and height 6, the volume inside the cylinder but outside the prism is? I know I need to subtract the volume of the square prism from the cylinder. The volume of the cylinder is 54pi. I am having trouble...
18. ### The expected area of the intersection between two shapes

Hi Everyone, Assume a unit space (the extent on each dimension is 1). Assume that we have two shapes in the space A and B. The area of A is 1/x and the area of B is 1/y (both x an d y are greater than or equal to 1). The shapes are randomly placed in the space. What is the expected area of...
19. ### Congruent Shapes

Hi, my friend helped me out with a problem before he had to go somewhere: He told me that since it says '6 congruent shapes implies that the height is 2/3 of the width.' I never got that. After that though, it's basic linear equations, I ended up with 100 centimeters. But how did he come...
20. ### Need help with slicing shapes in planes

Since I can't draw the picture I am given, I will describe the nature of the problem to see if anyone can help me out. I am given a solid, right circular cone. The cone is sliced perpendicular to its base through its vertex and the center of its base. Then I am asked which of the answer choices...