Question

Se stie ca a=11 di b+c=8. Calculati: ab+ac; 2a+3b+3c;10a+9b+9c;an+ac+25;an+ac-34;7b+7c+9a

Answer 1

ab+ac=11×4+11×4=44+44=88
2a+3b+3c=2×11+3×4+3×4=22+12+12=46
10a+9b+9c=10×11+9×4+9×4=110+36+36=182

Answer 2

a = 11  si  b + c = 8 

ab + ac = a ( b + c ) = 11 × 8 = 88 

2 a + 3 b + 3 c = 2 a + 3 ( b + c ) = 2 × 11 + 3 × 8 = 22 + 24 = 46 

10 a + 9 b + 9 c = 10 × 11 + 9 ( b + c ) = 110 + 9 × 8 = 110 + 72 = 182 

a b + a c + 25 = a ( b + c) + 25 = 11 × 8 + 25 = 88 + 25 = 113 

ab + ac - 34 = a ( b + c ) - 34 = 11 × 8 - 34 = 88 - 34 = 54 

7 b + 7 c + 9 a = 7 ( b + c) + 9× 11 = 7 × 8 + 99 = 56 + 99 = 155