Proportions and Similar Polygons Flashcards
(38 cards)
A common fraction
Ratio
The numerator of the first term of a ratio
The denominator?
Antecedent
Consequent
What are the two definitions for ratio
A common fraction
Comparison between 2 values
What is a proportion
A statement of equality between two ratios
The first and fourth terms of a proportion
The second and third
Extremes
Means
Fourth Proportional
The forth term of the proportion whose first three terms are the three quantities taken in order
Mean proportional
The two means equal in a proportion
Third proportional
When the two means of a proportion are equal then the last term is said to be the third proportional to the first and second terms
Property 1
The product of the means = product of the extremes
Fundamental Property of Proportions FPP
Property 1 Corollary 1
If three terms are equal to three terms of another proportion respectively then the fourth terms are equal
Property 2
If the product of two quantities is equal to the product of two other quantities either pair may be used as the means and the other pair as the extremes of a proportion
Axiom 14
Like powers or like roots of equal quantities are equal
Property 3
The mean proportional between two quantities is equal to the square root of their product
Property 4
The products of the corresponding terms of two or more proportions are in proportion
a:b = c:d ; m:n= p:q
Therefore:
(a)(m): (b)(n) = (c)(p): (d)(q)
Property 5
In a series of equal ratios the sum of the antecedents is to the sum of the consequents as any antecedent is to its consequent
Transformation 1
Alternation
Transformation 2
Inversion
Transformation 3
Addition consequent
Transformation 3 Corollary 1
Addition antecedent
Transformation 4
subtraction consequent
Transformation 4 Corollary 1
Subtraction Antecedent
Transformation 5
If four quantities are in proportion then like powers or like roots of these quantities are in proportion
If a line is drawn through two sides of a triangle parallel to the third side then it
divides the two sides proportionally
If a parallel is drawn through two sides of a triangle (parallel to the third side) then
either side is to one of its segments as the other side is to the corresponding segment