F ind
what you are solving for.
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Look for the question mark.
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Underline the information that
tells you what you are solving for.
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Name the variable (what you are
solving for) with a letter and write it after the question mark.
"I need to read this problem and
figure out what I am solving for. First I am going to look for a question
mark or a key word that signals what I am solving for. Here is the
question mark, and that tells me what I am solving for-the cost
of each CD. I'll underline that. Now I need to find the variable
(what I don't know) and choose a letter that represents the variable.
Well, what I don't know is the cost of each CD. I'm
going to pick the letter "c" to name the variable since the
variable represents the cost of a CD. I am going to
write "c" after the underlined sentence to remind me of the
variable."
A
sk yourself, "What is the important information?"
"Now I need to read through the word/story problem
and look for information that will be helpful for figuring out the
cost of each CD. I'm going to look for number phrases and circle them.
Let me seeŚ 'Carlos and Debbie each visited the local music store.'
Nope, no number phrase there. 'Carlos likes hip-hop music and bought
two CD's of his favorite singers.' Is there a number phrase in that
sentence? - Yep! two CD's. I'm going to circle that. And there is
a number phrase in the next sentence also. 'Debbie bought three R
& B CD's that featured some of her favorite singers.' There is no
number phrase in the next sentence, but I think it's important to
know that all the CD's cost the same amount. I'll need to remember
that. Finally, there is a number in the last sentence:
S et
up the equation.
"I've found the important information so I need to
write the equation. I'm going to write the circled number phrases from
the problem and then put blanks that I can put numbers in."
"I know that I need to put an addition sign in the
equation because it says 'Together they spent a total of $45.00 for
their CD's"
"Now I need to fill in the numbers. I am going
to use c for the cost of the CD's since that is my variable."
T ake
the equation and solve it using DRAW.
D
iscover the variable and the operation(s).
"There are two variables in this equation. I will
highlight the c's. There is one operation sign. It is an addition sign.
I am going to circle it."
R ead the equation.
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Combine like terms on each side of the equation.
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Figure out what the left side of the equation equals.
"Now I need to look for and combine like terms.
I see two numbers that have the variable c. I am going to add those
together. That will make the left side of the equation equal 5c."
A nswer
the equation, or draw and check.
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See example
of how to draw the solution.
"I need to draw the solution to the equation 5c
= 45. I don't know what c is, but I do know that I have 5 groups
of c, so I am going to draw 5 circles. I know that 5c equals 45,
so I am going to draw 45 tally marks. In order to solve the problem,
I need to divide 5 into both 5c and 45. Now I have c = 45 / 5. That
means I need to take the 45 tally marks and divide them equally
among the 5 groups. When I do that, I get 9 tally marks in each
circle. I have five groups of nine. That means that nine is the
value of c. Each CD was $9.00"
Write
the answer for the variable.
"Let me check my answer. I have solved the equation
and discovered that the value for c is nine, so I will substitute
9 for c in the equation. First I will combine like terms. 2c plus
3c is 5c. Now my equation is 5c =45. I am going to substitute
nine for the variable c. That means that 5c is five times nine,
or forty-five. I have solved the equation correctly because I
have 45 on both sides of the equation The cost of each CD was
9 dollars."
substituting the value 9 for c makes the equation:
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