Question

Se conidera numerele reale a,b,c astfel incat a+2b=11 si b+2c=16
a) a+3b+2c
b) a+b-2c
c) 2a+4b
d) 3b+6c

Answer 1

a+2b=11   ;    b+2c=16  ;

a)  a+3b+2c = (a+2b) + (b+2c) = 11+16 = 27 ;

b)  a+b-2c = a+2b - b-2c = (a+2b) - (b+2c) = 11-16 = -5 ;

c)  2a+4b = 2(a+2b) = 2*11 = 22 ;

d)  3b+6c = 3(b+2c) = 3*16 = 48 ;