Question

VA ROG ! ESTE URGENT ! OFER CORONITA ! EX 18

Answer 1

a) 3a+7b+4c= 3(20-b)+7b+4(30-b) = 60-3b+7b+120-4b=180

b) 5a+3b+2c= 5a + 3(33-a) + 2(11-a) = 5a+99-3a+22-2a = 121

Answer 2

18).

a).a+b=20

b+c=30

3a+7b+4c=?

7b=3b+4b

3a+3b+4b+4c=3(a+b)+4(b+c)=3*20+4*30=60+120=180

b).a+b=33

a+c=11

5a+3b+2c=?

5a=3a+2a

3a+2a+3b+2c=3a+3b+2a+2c=3(a+b)+2(b+c)=3*33+2*11=99+22=121