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Math Resources
Math Facts to Help you solve word problems:
Problems Involving Consecutive Integers
If a word problem asks for . . . then the variables could be set up like. . .
Consecutive integers
Consecutive even integers
Consecutive odd integers
x, x+ 1, x + 2, x+ 3, . . . .
x, x + 2, x + 4, x + 6, . . . . .
x, x + 2, x + 4, x + 6, . . . . .
(It all depends on how many and what information is included in the problem)
Slope Formula
slope  m 
y2  y1 rise change in y
vertical change
difference between y values




x2  x1 run change in x horizontal change difference between x values
What is a Linear Equation?
Linear Equations are two variable equations that have an exponent of 1 on each
of the variables; no variables in the denominators of any fractions; and no xy
terms.
Forms of Linear Equations
Slope-Intercept Form
Standard Form
Ax + By = C
xyintercept intercept
C
C
A
B
y = mx + b
Slope
Slope
y-intercept
A
B
m
b
Point-Slope Form
y  y1
m
x  x1
Slope
m
A point on
the line
(x1 , y1 )
How do you find the intercepts of a Linear Equation?
The x-intercept is the point (a, 0);
its where the line crosses the xaxis.
To find the x-intercept, plug-in a
0 for y in your linear equation.
The Learning Center at RCC
The y –intercept is (0, b) ; its
where the line crosses the y-axis.
To find the y-intercept, plug-in a o
for x in your linear equation.
Created by A McNeill
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Math Resources
Linear Equation Facts
Parallel Lines
Perpendicular Lines
Lines have equal slopes; the slopes
are the exact SAME number.
Parallel horizontal lines have
equations like y = a and y = b where a
 b; where a and b are any number.
Lines have slopes that are opposites
and reciprocals.
If one equation in a pair of
perpendicular lines is horizontal (of
the form y = a), then other has to be
vertical (of the form x = d); where a
and d are any number.
With perpendicular lines, if you
multiply the slopes you get -1 as your
answer.
Parallel vertical lines have equations
like x = a and x = b, where a  b;
where a and b are any number.
Inequalities Anyone?
Please note, inequalities solve just like an equation, but you must
remember to change the direction of the inequality symbol if you
multiply or divide by a NEGATIVE!
Graphing Single Variable Inequalities on a Number Line
< or >
< or >
Open Circle
Closed Circle
Interval Notation: ( )
Interval Notation: [ ]
It will always be true that if the variable is on the left side of the
inequality symbol, then shade the number line in the direction that the
inequality symbol is pointing. However, if the variable is on the right
side of the inequality symbol, then shade the number line in the
opposite direction that the symbol is pointing.
The Learning Center at RCC
Created by A McNeill