Question

1)Stiind ca a+b=8, aflati x in situatiile:
a) 3a+x+3b=17
b) 13a+xb+xa+13b=120

2) Aflati x si y stiind ca (x-2)×(y+1)=7

Answer 1

a) 3 (a+b)+x=17 3×8+x=17 x=17-24=-7 b) 13(a+b)+x(a+b)=120 13×8+x×8=120 104+8x=120 8x=16 x=2 La 2 nu prea înțeleg