Question

daca a-b=2 si b+c=6, sa se calculeze valoarea expresiei:3a+b+4c
VA ROG SA MA AJUTATI URGENTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
MULTUMMMEEEEESCCCCCC FFFFOOOOAAAARRRTTTEEE MMUUULLTT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!11

Answer 1

$b+c=6 \ \ \ |*4 \\\\ \underline{4b+4c=24} \\\\ a-b=2 \ \ \ |*3 \\\\ \underline{3a-3b=6} \\\\\\ \hbox{Se aduna cele 2 relatii subliniate} \\\\\\\4b+4c+3a-3b=24+6 \\\\\ \boxed{3a+b+4c=30}$

Answer 2

[tex]a-b=2|*3\\3*(a-b)=3*2\\3a-3b=6(1)\\b+c=6|*4\\4*(b+c)=4*6\\4b+4c=24(2)\\ Din\ (1)+(2):\\(3a-3b)+(4b+4c)=6+24\\3a+b+4c=30[/tex]