ection>
ALGEBRAIC EQUATIONS
Writing Algebraic Equations
Problem: Jeanne has $17 in her piggy bank. How much money does she need to buy a game that costs $68?
Solution: Let x represent the amount of money Jeanne needs. Then the following equation can represent this problem:
17 + x = 68
We can subtract 17 from both sides of the equation to find the value of x.
68 - 17 = x
Answer: x = 51, so Jeanne needs $51 to buy the game.
In the problem above, x is a variable. The symbols 17 + x = 68 form an algebraic equation. Let’s look at some examples of writing algebraic equations.
Example 1: Write each sentence as an algebraic equation
Sentence
A number increased by nine is fifteen.
Twice a number is eighteen.
Four less than a number is twenty.
A number divided by six is eight.
Algebraic Equation
y + 9 = 15
2n = 18
x - 4 = 20
k
6
= 8
Example 2: Write each sentence as an algebraic equation.
Sentence
Twice a number, decreased by twenty-nine, is seven.
Thirty-two is twice a number increased by eight.
The quotient of fifty and five more than a number is ten.
Twelve is sixteen less than four times a number.
Algebraic Equation
2t - 29 = 7
32 = 2a + 8
50
n + 5
= 10
12 = 4x - 16
Example 3: Write each sentence as an algebraic equation
Sentence
Eleni is x years old. In thirteen years she will be twenty-four years old.
Each piece of candy costs 25 cents. The price of h pieces of candy is $2.00.
Suzanne made a withdrawal of d dollars from her savings account. Her old balance was $350,
and her new balance is $280.
A large pizza pie with 15 slices is shared among p students so that each student’s
share is 3 slices.
Algebraic Equation
x + 13 = 24
25h = 200
350 - d = 280
15
p
= 3
An equation says that two things are equal. It will have an equals sign “=” like this:
x+2=6
Конец ознакомительного фрагмента.
Текст предоставлен ООО «ЛитРес».
Прочитайте эту книгу целиком, купив полную легальную версию на ЛитРес.
Безопасно оплатить книгу можно банковской картой Visa, MasterCard, Maestro, со счета мобильного телефона, с платежного терминала, в салоне МТС или Связной, через PayPal, WebMoney, Яндекс.Деньги, QIWI Кошелек, бонусными картами или другим удобным Вам способом.
