Math: Ratios and Proportions
Percent of Decrease
A Negative Percent of Change
Percent of Increase
A Positive Percent of Change
scale drawing
A drawing that is used to represent an object that is too large or too small to be drawn at actual size.
scale model
A model that is used to represent an object that is too large or too small to be built at actual size.
Percent of Change
A ratio that compares the change in quantity to the original amount
Tip or Gratuity
A small amount of money in return for service
Sales Tax
An additional amount of money charged on items that people buy
Percent Equation
An equation that describes the relationship between the part, whole and percent
Slope-Intercept Form
An equation written in the form y=mx+b where m is the slope and b is the y-intercept
cross products
In a proportion, you multiply the numbers diagonally across from each other
Percent Proportion
One fraction or ratio that compares part of a quantity to the whole quantity. The other ratio is the equivalent percent written as a fraction
Constant of Variation
The constant ratio in a direct variation
slope
The rate of change between any two parts on a line.
Direct Proportion/ Direct Variation
The relationship between two variable quantities that have a constant ratio
Side-Side-Side similarity
Two triangles are similar if all corresponding sides are proportional
Side-Angle-Side Similarity
Two triangles are similar if two of the corresponding sides are proportional and the included angles are congruent
Angle-Angle Similarity
Two triangles are similar if two of their corresponding angles are similar
y-intercept
Where the graph crosses the y-axis
function notation
a form where the input x is any real number and the output f(x) is read as the function of x
linear function
a function for which the graph is a straight line
nonlinear function
a function whose graphs are not straight lines
rate of change
a rate that describes how one quantity changes in relation to another
unit rate
a rate that is simplifies to have a denominator of 1
rate
a ratio that compares two quantities with different units
function
a relation in which each member of the input is paired with exactly one member of the output
scale factor
a scale written as a ratio without units in simplest form
relation
a set of ordered pairs
function table
a table used to organize the input values, output values, and function rule
proportion
an equation stating that two ratios or rates are equivalent
corresponding angles
angles that are in the same relative position
similar figures
figures that have the same shape but not necessarily the same size
equivalent ratios
ratios that have the same value
corresponding sides
sides that are in the same relative position
discount
the amount by which the regular price of an item is reduced
principal
the amount of money deposited or borrowed
simple interest
the amount paid or earned for use of money
function rule
the operations performed on the input value to get the output
constant rate of change
the rate of change in a linear relationship
scale
the ratio that compares the measurements of the drawing or model to the measurements of the real object
domain
the set of input values
range
the set of output values
dependent variable
the variable in a function that depends on the independent variable
independent variable
the variable in a function that is subject to choice
nonproportional
two quantities in which the ratios are not constant
proportional
two quantities with a constant ratio
indirect measurement
using similar figures to find the length, width or height of objects that are just too difficult to measure directly.
