Simple puzzle of mixed operation of rational numbers in junior high school mathematics problems 1-1-2.45x8+2.55x(-8) Why can't this formula be simplified, only 1-1-19.6-20.4
It's easy. You just need to change the minus sign of-2.45 to (- 8), and the formula is 1-1 + 2.45x (- 8) + 2.55x (- 8). It's easy to change it to 1-1 + (2.45 + 2.55) x (- 8), so that you won't feel dizzy. Another way is to put forward an eight minus signs in it, and the principle is the same
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