Zero Principle-Jornal#12

Zero Principle:


The zero principle says that the sum of two opposite integers is 0. Explain how the zero principle was used to find this sum.
(-5) + (+4) = (-1)


Answer:


This could be seen as -5 + 5 = 0;
                                   -5 + (4 + 1) = 0;
                                   -5 + 4 = -1.




Sovle the following using the principle of zer products
   

s^2+11s+28=0

s^2 + 4s + 7s +28=0


s(s+4) + 7(s+4)=0


(s+4)(s+7) = 0


using the principle of zero products:

s+4 = 0

OR

s+7 = 0


s = -7,-4