Question

stiind ca ab+ac=-56 si b+c=-13 aflati a

Answer 1

ab+ac=-56 / a(b+c)=-56 / -13a=-56|(-1) / 13a=56 / a= 56 supra 13 / a=4.3

Answer 2

ab+ac=-56
 b+c=-13 
ab+ac=a(b+c)
a(b+c)=-56
ax(-13)=-56
a=56:13