Teacher2Teacher 
Q&A #4120 
View entire discussion [<< prev] [ next >>]
From: quantgal <laurie.hailer@gmail.com> To: Teacher2Teacher Public Discussion Date: 2009062911:59:55 Subject: Re: mathematics Assuming your question is sincere, here is a response: Because you are taking the opposite of the absolute value of the product two times. The first time (minus times plus) you multiply a negative times the absolute value product , you will yield a negative answer. The second negative makes that product positive, when you take the opposite the second time. Example: 2 x 3 = (1 X 2) x (1 x 3) rearrange: (2 x 3) x (1) x (1) 2 x 3 = +6 Substitute and multiply by the first negative: (+6) x (1) = 6 Substitute and multiply by the second negative: (6) x (1) = the opposite of negative 6, which is +6. Therefore, minus times minus is plus.
Post a reply to this message

[Privacy Policy] [Terms of Use]
Math Forum Home 
The Math Library 
Quick Reference 
Math Forum Search