Grade 9 Math Key Words

Page 1

Solving Equations

Lowest Common Denominator

term

numerator

denominator

distributive property

expand

monomial, binomial, polynomial

BEDMAS

like terms, unlike terms

integers

coefficients

variables

inverse operations

isolate variable

substitute variable

reciprocal

cross-multiplying

constant

mixed/improper fractions

gathering like terms

Things to remember:

BEDMAS

simplify before multiplying fractions

reduce answer if possible

check negatives

Linear Relations

quadrant (1,2,3,4)

origin

x and y axis

independent/dependent

ordered pairs

rate of change/slope

undefined

negative/positive

table of values

partial/direct variation

linear relationship

interpolation/extrapolation

line segment

vertical/horizontal

y or x intercept

rise/run

perpendicular/parallel

break-even point

profit, revenue, cost

type 1, 2, 3 lines

Things to remember:

label the axis

appropriate scale

arrows on line

profit=revenue-cost

break-even point is when cost=revenue

let statement for word problems

"x" must not be in denominator

must be able to explain slope in context

check for integer errors

Modelling Linear Relationships

point of intersection

standard form

slope-y-intercept form

y in terms of x (y=?)

variables

break-even point

Things to remember:

no arrows on graphs

let statement

therefore statement

use slope in table of values

when finding intercepts, 'sub' into original equation

simplify

money should be expressed as decimal

use key words in answers (e.g. interpolate)

Algebra/Exponents

term

variable term

constant term

variable

coefficient

like/unlike terms

polynomials

exponent

base

power

Things to remember:

lowest terms

once you multiply, there should be no brackets

use empty brackets when substituting

try to keep 'x's and 'y's together

let statement

Geometry

angles

polygons

quadrilateral

supplementary

opposite angles'co-interior angles

rhombus

mid-segments/midpoints

parallel

bisect

complimentary

isosceles

alternate

transversal parallel lines

corresponding

exterior/remote angles

parallelogram

kite

diagonals

perpendicular

adjacent

Things to remember:

let and therefore statement

exact values

characteristics of shapes

Investigating Relationships

trend

outliers

line of best fit

correlation

mean fit line

convenience sampling

random sample

stratified sample

cluster sampling

finite difference

linear relationship

non-linear relationship

Things to remember:

use points of line of best fit to find slope

use different symbol on graph for mean point

outliers can be significantly below/above

if Y differences are positive, slope is increasing and vice versa

in stories about graphs include times, slopes, etc.

Key Words