## Tuesday, December 6, 2011

### EQUATION - A MATHEMATICAL SENTENCE THAT CONTAINS AN = SIGN

2 + 7 = 9
10 - 6 = 4
14 = 2 x 7
2 + x = 9
4 = k - 6
15 ÷ m = 3

Alot of the time we can find the solution to an equation with a variable without even working it out because we know our math facts. Though this isn't always true and it is extremely important that we know how to solve an equation.

You can use problem solving techniques as well as mental math to help you solve an equation, but sometimes the problems are too difficult to solve in our head so knowing the process is important, plus Mrs. White ALWAYS wants to see your work :).

So I guess I will tell you the most important things about solving an equation.
1.) What type of problem are you working (addition, subtraction, multiplication, or division)
2.) What is the opposite of the operation in the problem?
3.) Your goal is to get the variable alone on 1 side of the = sign, so you will need to move any numbers that are on the same side as the variable. To do this you will need to use the operation from step 2 to get the variable to the other side of the = sign.
4.) Remeber BALANCE - What you do to one side you must do to the other.
5.) Check to make sure your answer is the solution. Substitute your answer for the variable and work it out. If you get the same number of both sides of the equal sign then you were correct.

For example, x + 3 = 5 (notice how I use each step)
2. Opposite of Addition is Subtraction
3. & 4.) x + 3 = 5
- 3   - 3
x        = 2

Notice that I had to get the 3 away from the x so I did the opposite of addition to subtract 3 from both sides. When I subtracted 3 from 5, I got 2. To check and make sure 2 is the solution I will substitute it back into the original equation to check. When there is balance you know you were correct.

x + 3 = 5
2 + 3 = 5
5=5 When there is balance you know you were correct. J