Translating Sentences into Equations

1
Translating Sentences into Equations
Objective To translate word sentences into
equations
Applications of algebra frequently require you
to translate word sentences about numbers into
equations. Sometimes you can translate the
words in order, sometimes you cant. You may
need grouping symbols.
2
Twice the sum of a number and four is ten.
2
(n 4)

10
2(n 4) 10
3
When a number is multiplied by four and the
result is decreased by six, the final result is
10.
n
4
-
6

10
4
Three less than the number x is 12.
x
-
3

12
Remember, you have to be very careful when you
see the words less than.
x 3 12
5
Use the figure and the information below to write
and equation.
Perimeter the sum of all the sides
4
4
14 4 4 x
14 8 x
x
Perimeter 14
6
a. Choose a variable to represent the number
described by the words in parentheses.
b. Write an equation that represents the given
information
The distance traveled in 3 hours of driving was
240 km. (Hourly rate.)
Let r be the hourly rate.
Since rate x time distance, r 3 240, or 3r
240
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Assignment

• Page 20 22
• 1 34 (Written exercises)