a = 39
b + c = 36
--------------------/
3a + b + c = 3 · 39 + 36 = 117 + 36 = 153
a - ( b + c ) = 39 - 36 = 3
a + 2b + 2c = a + 2 ( b + c ) = 39 + 2 · 36 = 39 + 72 = 111
a + b + c = 39 + 36 = 75
a + 3b + 3c = a + 3 ( b + c ) = 39 + 3 · 36 = 39 + 108 = 147
2a + b + c = 2 · 39 + 36 = 78 + 36 = 114
2a + 5b + 5c = 2a + 5 ( b + c ) = 2 · 39 + 5 · 36 = 78 + 180 = 258
11)
a + b = 9
c = 3
----------------/
ac + bc = c ( a + b ) = 3 · 9 = 27
12)
a = 16
b + c = 25
ab + ac = a ( b + c ) = 16 · 25 = 400
2a + 3b + 3c = 2a + 3 ( b + c ) = 2 · 16 + 3 · 25 = 32 + 75 = 107
***In unele cazuri m-am folosit de metoda factorului comun, iar in altele doar am inlocuit!
