algebraic equations

 Sorry last post was a mistake. Today's topic is algebraic equations. The vocabulary for today is the words variable and equation. A variable is a letter that is used to represent an unkonwn number.  An equation is a number sentence that shows that two expresions are equivalent. There are three steps to solving algebraic equations. Step 1  -Ask yourself what is being done to my variable. Step 2 - do the inverse operation of what is being done to the variable. Here is an example the inverse operation of addition is subtraction and the inverse operation of multiplication is division. It is the opposite if division or subtraction is being done. Example of doing this is here.

                                                                                                6=x-9

                               Subtraction is being done to the variable so we do addition. Like this...

                                                                                                

                                                                                              

                               

                                 6+9=15 and since 9 is being subtracted adding nine cancels the nine out. 

Since nine is canceled out all we have left is 15=x which is true we found the variable x=15. All step three is write out the variable equals whatever the answer is. That is it that is how you solve it.

                                                                        That looks likes this

                                                                                       6=x-9

                                                                                     +9=x-9 

                                                                                         15=x

                                                    Now I will teach you how to check it 

First write the equation. Next plug in your answer. Then, add it up and write your answer equals the answer to the equation. Finally write the variable = you answer and that is how you check it Example 

                                                                                    6=x-9

                                                                                    6=15 -9

                                                                                      15=15

                                                                                       x=15

You could use this in life when you fill up your gas tank.If you have 20 dollars and gas is 3.50 a gallon and you want to know how many gallons you can buy you use algebra to find the answer.

algebraic equaitions

Today's topic is factors and greatest common factors. Let's start with factors. Your vocabulary for factor lesson is the word factor. A factor is a number that divides evenly into another number. How do you find them? The number one is a factor of every number. Two is a factor if the number is even. Three is a factor if the sum of the numbers in the number are divisible by three. Four is just divide by two twice. Five is a factor if the number ends in 0 or 5. Six if the number is divisible by 3 and 2. Sevens are hard because it is a prime number. Eight is factor if you can divide it by four twice. Nine if the sum of the digits is divisible by 9. Ten if it the number ends in 0. The hard part is finding the factors other factor. You do this by dividing the factor into the number that your trying to find out the other factor of.  That's factors.To find the GCF you must write out all the factors of the two numbers to find the GCF. The highest idenitical factor of the set is the GCF. That's the GCF. Here are two cool links. http://www.helpwithfractions.com/greatest-common-factor.html and http://amby.com/educate/math/2-1_GCF.html