Question

afla numerele necunoscute.a)a:b=3rest5 si a- b=2 b)a:b=8rest3 si a+ b=9

Answer 1

a=b·3+5
a-b=2
3b+5-b=2
2b=2-5
b=-3/2
a=1/2

a=8b+3
a+b=9
8b+3+b=9
9b=9-3·
9b=6
b=2/3
a=25/3

Answer 2

a)   a=3b+5  => a - b = 2 adica: 3b+5 - b =  2 => 2b = -3 deci  b = -3/2 ;
      ↑
      a = 3×(-3/2)+5 = -9/2+5 = (-9+10)/2 = 1/2 ;

b)  a=8b+3  =>  a+b=9  adica:  8b+3 + b = 9 => 9b = 6  deci: b = 6/9 = 2/3;
      ↑
     a = 8*2/3+3 = (16+9)/3 = 25/3 .