Basic terms
Variables
Expressions
Equations
Evaluate expressions using variables
Solve equations using basic
operations
One-step equations
Two-step equations
Add
Subtract
Multiply
Divide
Distributive property
Multiply binomials
FOIL
Square binomials
Basic terms
Variables
Expressions
Equations
Evaluate expressions using variables
Solve equations using basic
operations
One-step equations
Two-step equations
Add
Subtract
Multiply
Divide
Distributive property
Multiply binomials
FOIL
Square binomials
Evaluating Expressions Using Variables
A variable is a letter or symbol that represents a number. To evaluate
a variable expression, substitute the given value for the variable. If
you have a
number and a variable side by side (3r) or if you have two variables
together (ab), this means to multiply them together.
3r means to multiply the "3" with the value of "r"
ab means to multiply the value of "a" with the value of "b"
Solving Addition Equations
To solve addition equations, use the inverse operation which is subtraction.
Subtract the number on the side with the variable from both sides of the
equation to get the answer.
a + 12 = 51
a +12 - 12 = 51 - 12
a = 51 -12
a = 39
Solving Subtraction Equations
To solve subtraction equations, use the inverse operation which is
addition. Add the number on the side with the variable to both sides of
the equation to get
the answer.
s - 13� =� 21
s - 13 + 13 = 21 + 13
s = 21 + 13
s� =� 34
Solving Multiplication Equations
To solve multiplication equations, use the inverse operation, which
is to divide. Divide both sides of the equation by the number with the
variable to get the
answer.
5m� =� 15
5m ÷ 5 = 15 ÷ 5
m =� 3
Solving Division Equations
To solve division equations, use the inverse operation which is multiplication.
Multiply both sides of the equation by the number under the variable to
get the
answer.
d/3 = 6
d/3 * 3 = 6 * 3
d/3 * 3/1 = 6 * 3
d = 18
Solving Two-Step Equations
If an equation contains more that one operation, then it is solved
in stages. First use the inverse of the addition or subtraction, and then
use the inverse of the
multiplication or division.
First:
3c + 12� =� 36
3c + 12 - 12 = 36 - 12
3c = 24
Second:
3c = 24
3c ÷ 3 = 24 ÷ 3
c = 8
(other skills to be added)