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Home : 2008 : February : 4

I found some :)
By saraebeth

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Anyone have anything else? This makes sense to me, different than how I learned but I think the kids will understand this way better than the way the TE says to teach them.

ADDITION:

If the signs are the
same then you add the two numbers and keep the
sign.

Ex. 6 + 2 = 8 or -6 + -2 = -8

If the signs are different, subtract the two numbers and take the sign
of the larger number.

Ex. -6 + 2 = -4 or 6 + -2 = 4

SUBTRACTION:

Change the sign of the second number, then add the two numbers using the
rules for addition, above.

Ex. 6 - 2 = 6 + (-2) = 4
Ex. -6 - -2 = -6 + (+2) = -4
Ex. -6 - 2 = -6 + (-2) = -8
Ex. 6 - -2 = 6 + (+2) = 8



-Doctors Sonya and Jennifer, The Math Forum
Check out our web site!
http://mathforum.org/dr.math/

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