If your total wealth is $4 and then you go into debt for $11 what is your total wealth? Obviously you are now in debt for $7 which can be written -$7. So what has happened is you have added a negative $11 to your wealth of $4 and this can be calculated as
$4 + (-$11) = -$7 it could also be done -$11 + $4 = -$7
In algebra we don't deal with subtraction problems instead we change all subtraction problems to addition problems and then use the rules of addition to solve the problems. Lets look at a problem and see if you can write the rules for subtraction.
8 - (-3) = 11 try to figure out what we did. answer
Try these problems. 1) 18 - (-7) = 2) 15 - (-3) = 3) 9 - (+7) = 4) -8 - (+ 3) = answer
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