Prequisites for Algebra
Algebra is a difficult enough subject. Don't make it worse by not knowing what you should know when the class starts.
The most important prerequisite is to learn the math facts.
Multiplication
Division
Adding and Subtracting Numbers
Also, the "fact monster" is a great site on the internet to practice the math facts.
If you need your fingers to multiply, add or subtract then you do NOT adequately know your math facts. You should feel very comfortable with the following subjects/concepts:
Addition of integers
8+5 17+48 1456+3201 5401+10223
121+2232 88+44 329123+9908887
If any of the above give you a problem you need to spend time understanding
how to do these problems. Help
Subtracting integers
8-5 217-48 3456-3201 15401-10223
3121-2232 88-44 329123-99887
If any of the above give you a problem you need to spend time understanding how to do these problems.
Adding/subtracting negative numbers
-7+6 9-12+4 90-100+2 -11-30-4 -34-48-2+200
6-2 -2+6 -3-5-12+30 -44-12-3
If any of the above give you a problem you need to spend time understanding
how to do these problems. The number line is always a good tool in solving addition and subtraction problems.
Handling signs in addition/substraction and mult/div
-4-(-4) 5+(-10) -8-(-10) -100-(-200)
-4-8-(-7) -12-30+(-20) -(-30)+32
If any of the above give you a problem you need to spend time understanding
how to do these problems.
Dividing integers
9/3 36/9 45/5 54/6 18/2 42/6 63/7
81/9 40/10 56/8 42/7 27/3 32/4 22/22
If any of the above give you a problem you need to spend time understanding
how to do these problems, which is just basically memorizing the division facts.
To recap what multiplication and division are though, lets look at multiplication.
Consider 6 + 6 + 6 + 6 that is 6 added 4 times or 4 sixes.
And multiplication is just a shortcut for doing such
addition.
6 + 6 + 6 + 6 is the same as 4 times 6 or 4 * 6 or 4(6)
which are different ways to indicate multiplication.
And division is the opposite of multiplication.
The problem 24 / 6
24 divided by 6 can also be expressed as how many times
can six be subtracted from 24.
24 / 6 is, of course, equal to 4. And 6 can be subtracted
from 24 four times, as illustrated below.
24 - 6 = 18 1 time
18 - 6 = 12 2 times
12 - 6 = 6 3 times
6 - 6 = 0 4 times
Also, note that there is zero (0) remaining.
Sometimes in division there is a remainder. Consider 26 / 4 which is 6 with a remainder of two. Or
26 - 4 = 22 1 time
22 - 4 = 18 2 times
18 - 4 = 14 3 times
14 - 4 = 10 4 times
10 - 4 = 6 5 times
6 - 4 = 2 6 times and we cannot subtract 4
any more, but there is 2 left
over as a remainder.
Multiplying by 10, 100, 1000, etc
When multiplying by 10, 100, 1000, etc ....
just count the zeros and move the decimal
point that many places to the right in the
other number. That is to say:
34 * 100
Count the zeros = 2
Move decimal in 34 (which is 34. ) to the right twice
3400 Answer
1047 * 10000
Count zeros = 4
Move decimal 4 times to the right
10470000 Answer
This rule also works for decimal numbers. Say,
45.38 * 10
Count zeros = 1
Move decimal one time to the right
453.8 Answer
Dividing by 10, 100, 1000
Dividing by 10, 100, 1000, etc is very similar multiplying with one little difference. When dividing by 10, 100, 1000, etc .... just count the zeros and move the decimal point that many places to the left in the other number. That is to say:
3496 / 100
Count the zeros = 2
Move decimal in 3496 (which is 3496. ) to the left twice
34.96 Answer
104768 / 10000
Count zeros = 4
Move decimal 4 times to the left
10.4789 Answer
This rule also works for decimal numbers. Say,
45.38 / 10
Count zeros = 1
Move decimal one time to the left
(since it is division)
4.538 Answer