algebra
introduction to alebra
Algebra is known to be an intimidating topic, but it is actually not that difficult. Algebra is the study of mathematical symbols and the rules for manipulating these symbols. As such, it includes everything from elementary equation solving to the study of abstractions such as groups, rings, and fields. Here is an introduction to algebra!
A puzzle
What is the missing number?
____ - 2 = 4
OK, the answer is 6, right? Because 6 − 2 = 4. Easy stuff.
Well, in Algebra we don't use blank boxes, we use a letter (usually an x or y, but any letter is fine). So we write:
Well, in Algebra we don't use blank boxes, we use a letter (usually an x or y, but any letter is fine). So we write:
X - 2 = 4
It is really that simple. The letter (in this case an x) just means "we don't know this yet", and is often called the unknown or the variable.
And when we solve it we write:
And when we solve it we write:
x = 6
Why Use a Letter?
How to Solve
Algebra is just like a puzzle where we start with something like "x − 2 = 4" and we want to end up with something like "x = 6".
But instead of saying "obviously x=6", use this neat step-by-step approach:
Here is an example:
But instead of saying "obviously x=6", use this neat step-by-step approach:
- Work out what to remove to get "x = ..."
- Remove it by doing the opposite (adding is the opposite of subtracting)
- Do that to both sides
Here is an example:
Why did we add 2 to both sides?
Next, multiply 7 by 5. This time, 5 7 is 35. But you also need to add the 2 that you carried over, which makes the result 37. Because 5 and 7 are the last numbers to multiply, you don’t have to carry, so write down the 37 — you find that 53 7 = 371:
another puzzle
x + 5 = 12
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quizzes
Now practice on this Simple Algebra Worksheet and then check your answers on the page after. Try to use the steps we have shown you here, rather than just guessing!
Question 1
Question 2
Question 3
Question 4
Question 5
Question 6
Question 7
Question 8
Question 9
Question 10
Question 1
Question 2
Question 3
Question 4
Question 5
Question 6
Question 7
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Question 10