Lesson HOW TO multiply negatives
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The rule of how to multiply negatives is simple: <CENTER><TABLE WIDTH=50% border=1><TR><TD>To multiply a negative number by any number, take the (positive) opposite of the negative number and multiply it by the other number, and take the opposite of that</B></TD></TR></table></CENTER> <H4>Negative by positive number</H4> For a case where a negative number is multiplied by a positive, the rule above can be restated as: take the positive number, and the negative WITHOUT the minus sign, multiply them and add the inus sign to the product. Example: multiply 5 and -3. Take 5 and -3 without the "-" sign: 5 and 3 Multiply them: 5*3 = 15. Add the minus sign: -15. Conclusion: <B>Product of a negative and a positive is always a negative number</B>. <H4>Negative by negative number</H4> When you have to multiply two negative numbers, such as (-5) * (-3), the rule above should be applied twice: (-5)*(-3) is the opposite of 5*(-3), which is the opposite of the opposite of 5*3. 5*3 is 15 Opposite of 15 s -15. Opposite of opposite of 15 is opposite of -15, and opposite of -15 is 15 again. Conclusion: <B>Product of a negative multiplied by negative is always POSITIVE</B>. Here's a handy table: sign of result when we multiply <TABLE cellspacing=10 align=center> <TR><TD>Multiply:</TD><TD align=center>Positive</TD><TD align=center>Negative</TD></TR> <TR><TD>Positive</TD><TD align=center><FONT SIZE=+4 COLOR=red>+</FONT></TD><TD align=center><FONT SIZE=+4 COLOR=red>-</FONT></TD></TR> <TR><TD>Negative</TD><TD align=center><FONT SIZE=+4 COLOR=red>-</FONT></TD><TD align=center><FONT SIZE=+4 COLOR=red>+</FONT></TD></TR> </TABLE> Examples: 2*3=6 2*(-3) = -6 (-2)*3 = -6 (-2)*(-3) = 6