Question

1)daca x=7 si 2a+6bx=98 aflatia+3b. 2)dacă a+b=12 si c=9 aflati a•c+b•c. 3) dacă a=2sib+c=13 aflati 5•a+3•b+3•c

Answer 1

1. 2(a+3b)×7=98 => a+3b= 98:7:2 => a+3b= 14:2 => a+3b= 7
2. c( a+b)= 9×12= 108
3. 5a+3(b+c)= 5×2+3×13= 10+39= 49