Polyhedron / Poliedros

A polyhedron is a solid with flat faces (from Greek poly- meaning "many" and -edron meaning "face"). Each face is a polygon (a flat shape with straight sides). Cuando hablamos de figura geométrica, lo hacemos en dos dimensiones (2D): largo y ancho, pero cuando hablamos de un cuerpo geométrico lo hacemos en tres dimensiones (3D) largo, ancho y alto. Es así como dejamos de hablar de una geometría plana, para introducirnos en el estudio de...

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Sexagesimal system

     Sexagesimal is a numeral system in which each unit is divided into  60 units of lower order, that is to say, it is a base-60 number system The sexagesimal system was used by the Sumerians and Babylonians.  It is currently used to measure time and angles 1 h 60 min 60 s 1º 60' 60'' Converting Sexagesimal into Decimal Form Convert 3 hours, 36 minutes, 42 seconds to seconds. Converting Decimal...

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Equations

What is an Equation An equation says that two things are equal. It will have an equals sign "=" like this: x+2=6 That equation says: what is on the left (x + 2) is equal to what is on the right (6) So an equation is like a statement "this equals that" Parts of an Equation So people can talk about equations, there are names for different parts (better than saying "that thingy there"!) Here we have an equation...

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Proportionality

Proportions To practice1 To practice2 Proportion says that two ratios (or fractions) are equal. Example:   So 1-out-of-3 is equal to 2-out-of-6 The ratios are the same, so they are in proportion. Example: Rope A ropes length and weight are in proportion. When 20m of rope weighs 1kg, then: 40m of that rope weighs 2kg 200m of that rope weighs 10kg etc. So: 201 = 402 Sizes When...

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SCIENTIFIC NOTATION

Scientific Notation Scientific Notation (also called Standard Form in Britain) is a special way of writing numbers: Like this: Or this: Scientific notation is a way of writing numbers that are too big or too small to be conveniently written as ordinary numbers. Scientific notation is commonly used in calculators and by scientists, mathematicians and engineers. In scientific notation all numbers are written...

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