Question

stiind ca x=5 si y+z=14,calculti :a)x+2x+2z; b)5x+3y+3z.

Answer 1

x=5
y+z=14

a) x+2y+2z=
    =5+2(y+z)=
    =5+2*14=
    =5+28=33

b) 5x+3y+3z=
   =5*5+3(y+z)=
   =25+3*14=
   =25+42=67

Answer 2

x+y=56
y+z=88
x+z=80
a) x+2y+2z=x+2(y+z)= 5+2*14=5+28=33
b) 5x+3y+3z=5x+3(y+z)=5*5+3*14=25+42= 67