Algebra I in Simple English/Introduction to Basic Algebra Ideas/Simple Operations
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[edit] Vocabulary
Operation
Equals Sign
Adding
Subtracting
Multiplying
Dividing
[edit] Lesson
An ''operation" is a thing you do to numbers. You use signs like: +, -, *, or / for operations.
The Equals Sign is not an operation. You use the " = " sign for the Equals Sign. It is a special sign that you put between two things that are the same.
[edit] Adding
Adding is a way to put two numbers together. You use the " + " sign for the adding operation. If you have 5 apples and a friend has 6 apples, you and your friend have 11 apples. This is
5 + 6 = 11 using the signs of Math, and is read "five plus six equals eleven".
Order is not important when adding. 2 + 3 is the same as 3 + 2.
[edit] Subtracting
Subtracting is a way of taking a number out from another number. It is the opposite of adding. You use the " - " sign for the subtracting operation. If you have 5 apples and give 3 to a friend, you then have 2 apples. This is 5 - 3 = 2 using the signs of Math. Read this "five minus three equals two".
Order is important when subtracting. 3 - 2 is not the same as 2 - 3.
[edit] Multiplying
Multiplying is a way of adding a number many times. You use the " × " or ""•"" sign for the multiplying operation. If you have 4 apple trees and every tree has 25 apples, you have 100 apples. This is 4 × 25 = 100 or 25 + 25 + 25 + 25 = 100 in the signs of Math. The first way is shorter and easier to use.
Multiplying 25 by 4 is the same as adding 25, 4 times or adding 4, 25 times.
4 x 25 = 100 should be read "four times twenty-five equals one hundred".
Order is not important when multiplying. 2 × 3 is the same as 3 × 2.
[edit] Dividing
Dividing is a way of subtracting a number many times. It is the opposite of multiplying. You use the " / " sign for the dividing operation. If 3 friends take an equal part of a bag of 12 apples, every friend gets 4 apples. Or, you may take away (subtract) 3 apples from the bag of 12 apples, exactly 4 times until the bag is empty. This is 12 / 3 = 4 or 12 - 3 - 3 - 3 - 3 = 0 in the signs of Math.
Order is important when dividing. 3 / 2 is not the same as 2 / 3.
[edit] Example Problems
3 + 4 = 7
5 - 3 = 2
6 × 2 = 12
13 + 14 = 27
21 - 9 = 12
8 × 3 = 24
[edit] Practice Games
[edit] Practice Problems
6 + 8 =
3 + 4 =
10 + 15 =
28 + 13 =
12 - 5 =
16 - 3 =
7 x 5 =
8 x 4 =
6 x 6 =
