Definition of Similarity and Congruency?

Question

Examples of How magician and Designers make use of Similarity and Congruency?

Answer 1

two shapes are said to be similar if they have proportionate sides - their sides are proportional (this indirectly implies their angles are EQUAL & not proportinal)


for example all equilateral triangles are similar ,all squares are similar

a triangle with sides 2 , 4, 6 is similar to one with 6 , 12 , 18



congruency of two shapes implies they are exactly the same - all sides equal & all angles equal


all congruent shapes are similar but all similar shapes need not be congruent

Answer 2

Congruency means that both shapes are exactly the same: If you lay one over the other, they will both have exactly the same shape (each side on one of the figures will have a side on the other figure of the same length, each angle will have an angle on the other figure that will be the same as on the original figure). The best way to imagine this is to have two figures that look exactly the same and are exactly the same size.

Similarity will have the same angles, but the sides can be of different lengths, normally all of the sides of the original figure will be multiplied by a factor to create the other figure. The best way to see this could be a picture that you resize, in a certain percentage, keeping the ratio on each side.

Answer 3

Similar shapes have equality of respective angles and therefore proportional sides. Congruent shapes have both equal angles and equal sides. (If you placed one on top of the other they would not be distinguishable.)
The concepts of similarity and congruency are not limited to triangles, or, for that matter plane objects.

Answer 4

Similarity is two or more figures who are the same shape but not the same size. Congruency is two or more figures who are the same size and shape. Congruency tests are:
SAS (side angle side- angle is included between the two given sides)
SSS (side X3)
AAS (angle angle side)
RHS (right-angle hypontenuse side)