2-5 Solving Equations with the Variable on Each Side

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2-5 Solving Equations with the Variable on Each
Side
Algebra 1 Glencoe McGraw-Hill Linda
Stamper
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Since variables represent numbers, you can add or
subtract variable terms. Remember the basic rule
for solving equations
Whatever you do to one side of the equal sign,
you must also do to the other side of the equal
sign.
To solve equations that have variables on both
sides of the equal sign, first collect the
variable terms on one side of the equation.
Collecting the variable terms on the side with
the greater variable coefficient will result in a
positive variable.
An equation is not solved if the variable is
negative.
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Solve .
Check
Write the problem.
Collect variable terms on one side.
Undo addition and simplify.
?
What is the greater variable coefficient?
Undo multiplication and simplify.
On a test, do not check your answers until you
have completed all the problems. Then formally
check your equations. This is good test taking
strategy so you do not spend too much time on one
problem and fail to finish the test.
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Solve.
Write problem.
Distribute and combine like terms.
Collect variable terms on one side.
Isolate the variable using inverse operations.
Copy in your spiral notebook!
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Please take a highlighter or red pencil and draw
a line through the equal signs for the problem
you just copied. Does it produce a straight line?
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Solve.
Example 3
Example 1
Example 2
Leave the fraction improper. It must be in lowest
terms.
Use good form place the negative out front!
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Example 4 Solve.
Example 5 Solve.
Example 6 Tripling the greater of two
consecutive even integers gives the same result
as subtracting 10 from the lesser even integer.
What are the integers?
I should write let statements for this word
problem.
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Solve.
Example 4
Example 5
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Example 6 Tripling the greater of two
consecutive even integers gives the same result
as subtracting 10 from the lesser even integer.
What are the integers?
Let f first integer, Let f 2 second integer
The integers are -8 and -6.
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Example 7 One half of a number increased by one
is six less than one fourth of the number. Find
the number.
Example 8 Sixteen more than three fourths of a
number is one eighth of the number less than 2.
Find the number.
-2
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Example 9 Solve. Round to the nearest tenth.
Example 10 Solve. Round to the nearest tenth.
You need to divide to what decimal position in
order to round to tenths?
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Homework
2-A9 Pages 101 1130