Răspunsuri

2014-10-30T16:45:43+02:00
1. xz+yz=z*(x+y)=z*23=15*23=345. 2.xz-yz=z*(x-y)=z*12=10*12=120. 3.ab+ac=420/a*(b+c)=420/a*14=420/a=30. 4.ab-ac=135/a*(b+c)=135/9*(b+c)=135/b+c=15. Sper ca te-am ajutat ;)
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