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Welcome to solving simple equations using addition and subtraction.

Solving equations is very easy once you learn how to do them. First you must learn the rules of all equations. Now some of the rules do not apply to adding and subtracting equations so we will tell you the ones that do. First an equal quantity may be added to each side of an equation, which is called the inverse of subtraction. Second an equal quantity may be subtracted from an equation, Which is called the inverse of addition. For example,
  • 44=44
  • 44-12=44-12
  • 44=44
  • 44+12=44+12

So this is how you solve equations. IF you had a problem like this, x+7=12
you would subtract 7 from each side like the problem -7 -7
then you get: x=5
So five is your answer
To check your answer you can plug your number into the original equation like this 5+7=12 which is a true equation.

Let us give you a problem that you can relate to. The footbal on the field is on the 37 yd line. The offense runs it x yds to end up on the 13 yd line how many yds the they rush the ball? This is a very easy equation. First you must extract your information. It was on the 37 yd line they ran it x yds they ended up on the 13 yd line. So you can set up your equation like this. 37-x=13 How do you solve this?
First you do your inverse of addition -37 -37
Then you come out with x=-24
So to check you put in your number into the equation 37-24=13 which is true.

For extra practice/help please visit these sites
http://www.math.com/school/subject2/practice/S2U3L1/S2U3L1Pract.html
http://www.phschool.com/atschool/academy123/html/bbapplet_wl-problem-430704.html
ttp://www.phschool.com/atschool/academy123/html/bbapplet_wl-problem-430701.html
http://www.berghuis.co.nz/abiator/maths/sa/saintegersubtract2.html