Daca a+b+c=15 si x=2, calculaţi expresiile:

a) 2a+2b+2c+10x=
b) 13x+5a+5b+5c.

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Pai daca a+b+c=15 => ma refer la punctul a) 2(a+b+c ) + 10*2= 2*15+10*2= 30+20=50
a+b+c=15, x=2 a)inlocuim in 2a+2b+2c+10x=>30+20=50 b)inlocuim in relatia 13x+5a+5b+5c =>26+75=101
Si punctul b) 13*2+5(a+b+c) = 26 +5*15= 26+75=101
2x(a+B+c)=>30. 10x =>20. 2a+2b+2c+10x=50. 13x=26. 5x(a+b+c)=75 =>. 101

Răspunsuri

2014-02-01T17:09:01+02:00
A) 2a+2b+2c+10x=2*(a+b+c)+10x=2*15+10*2=30+20=50
b)13x+5a+5b+5c=13x+5*(a+b+c)=13*2+5*15=26+75=101
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