Afla numarul necunoscut:a+13=28;b-17=40;60-c=26;29+d=39

Răspuns :

a+13 = 28 => a = 28-13 => a = 15

b-17 = 40 => b = 40 + 17 => b = 57

60-c = 26 => c = 60-26 => c = 34

29+d = 39 => d = 39-29 => d = 10

a+13=28 => a = 28-13 = 15;

b-17=40 => b = 40+17= 57;

60-c=26 => c = 60 - 26= 34;

29+d=39 => d = 39 - 29 = 10;