Răspuns :
a×b + a×c = 91 + 260 = 351
a× ( b +c) = 351
a×( b +c) × 2 = 351 ×2 =702
a× ( b +c) = 351
a×( b +c) × 2 = 351 ×2 =702
[tex]a*b=91 \\ a*c=260 \\ a*(b+c)*2=? \\ a*(b+c)=a*b+a*c=91+260=351 \Rightarrow a*(b+c)=351 \\ a*(b+c)*2=351*2=702 \Rightarrow a*(b+c)*2=\boxed{702}[/tex]