Basic Algebra – Lesson 2
by Elaine Ernst Schneider
Objective(s): By the end of this lesson the student will be able to: translate a word sentence into a mathematical expression.
PreClass Assignment: Completion of Basic Algebra – Lesson 1
Resources/Equipment/Time Required:
Outline:
In the first lesson, you learned that numbers and variables form sentences, or algebraic “expressions.” When you take information from a sentence and turn it into a mathematical expression, it is called “translating.”
A place to begin:

 When you write algebraic expressions, use +, , and = signs. For division, use / , the same way you know that when you see a fraction, it means to divide the top number by the bottom number.
 For multiplication, write the expression with no symbol or sign between them as the X (multiplication) symbol can be confused with the variable x. For example 3 times the variable y should be written 3y. You can also use parentheses to indicate multiplication. This is especially useful in longer problems such as (3y)(42x).
 When you want to multiply something AFTER another expression has been done first, use parenthesis. For example, if you want to add x and y and THEN multiply the result by 7, write it this way: 7(x + y).
 To translate from language to a math expression, read the sentence carefully. Then decide what operations it will take to reach a solution. Write this into an algebraic expression.
Let’s Get Started:
Here is the word problem:
I am stocking shelves at a Tshirt store. I have been given eight boxes of Tshirts. There are 25 Tshirts in each box. My instructions are to take one Tshirt from every box and set it aside to be given to the poor. How many Tshirts will be left for me to put on the store shelves after I sort out the Tshirts to be given to the poor?
Here is the algebraic expression:
8(251)
8(24)
192
If you don’t know the number of Tshirts in each box, then substitute the variable x for that. Then the expression would look like this:
8(x – 1)
Now it’s time for you to try a few.
Assignment(s) including Answer key:
EXERCISE:
 Katie is 21 years old. Write an algebraic expression that tells how old she will be in five years. Let x represent that age. Solve from your expression.
 One hamburger costs x cents. Write an algebraic expression that tells how much 4 hamburgers will cost.
 Sandy is 21 years old. Al is five years older. How old will Al be in five years? Let x represent Al’s age in five years. Solve for x.
 I have ten hats that cost $47.50 for all of them. Write an algebraic expression to show how much one of those hats cost, letting y represent the answer. Solve for y.
 I have ten hats that cost $47.50 for all of them. How much will I have to sell EACH hat for to make a profit of $1 on each? Set it up in an algebraic expression to solve.
ANSWER KEY Click Here:
PreRequisite To: Basic Algebra – Lesson 3 Solving for X
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