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Do Now 10/29/13
 Copy HW in your planner.
 Text page 470, #8-34 evens
 In your notebook, answer the following question.
 Sally Sue just received her cable bill from Comcast. The bill for
the month is a total of $114.50. Comcast charges $5.00 for
each movie ordered “On Demand.” Sally Sue can’t remember
how many “On Demand” movies she ordered in the month? If
Sally Sue’s normal bill is $89.50, how many “On Demand”
movies did she order?
 Can you think of an equation to help you solve this question?
Use the variable “m” for movies.
Objective
 SWBAT solve two-step equations using
algebra
Equation
2 s + 8 = 20
Left side
‘s’ has to be 6 in order
to make the equation
balanced.
Like a scale, the left
side and right side must
be the same in order to
be balanced!
Right side
Equation mathematical sentence
with an equal sign
Like a scale,
both sides must be
EQUAL in order
to be balanced.
Section 11.1
“Solving Two-Step Equations”
How can you get the “unknown” by itself?
3x + 5 = -19
“Undo” operations by using the INVERSE (opposite)
operations to both sides of the equation.
Solving Two-Step Equations
STEP 1STEP 2STEP 3STEP 4-
“Undo” addition and/or subtraction.
“Undo” multiplication and/or division.
Solve for the variable.
Check your work.
Solving Two-Step Equations…
Isolate the variable! Get ‘x’ by itself.
To get the ‘x’ by
itself first get rid
of “adding 5.”
3x + 5 = -19
-5
-5
Do the opposite.
“Subtract 5.”
Whatever you do to
one side of the equation
you must do the other side.
To get the ‘x’ by
itself get rid
of “multiplying by 3.”
Do the opposite.
“Divide by 3.”
3x = -24
3
3
x = -8
Check Your Work!
3x + 5 = -19
x = -8
3(-8) + 5 = -19
Are both sides equal?
“Two-Step”
Millionaire
Homework
Text page 470, #8-34 evens