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 can’t. You
may need grouping symbols.
Twice the sum of a number and four is ten.
2
(n + 4)
2(n +4) = 10
= 10
When a number is multiplied by four and
the result is decreased by six, the final
result is 10.
4 n - 6 = 10
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
Use the figure and the information
below to write and equation.
Perimeter = the sum of all the sides
14 = 4 + 4 + x
14 = 8 + x
4
4
x
Perimeter = 14
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
Assignment
• Page 20 – 22
– #1 – 34 (Written exercises)