Question

Daca x=3 si y+z=10,calculeaza: a) 7•x+7•y+7•z; b) 17•x+17•y+17•z-10; c)5•x+10•y+10•z; d)100•x-(9•y+9•z).

Answer 1

7*x+7*y+7*z=7*x+7*(y+z)=7*3+7*10=21+70=91
17*x+17*y+1*7z-10=17*x+17*(y+z)-10=17*3+17*10-10=51+170-10=211
5*x+10*y+10*z=5*x+10*(y+z)=5*3+10*10=15+100=115
100*x-(9*y+9*z)=100*x-9(y+z)=100*3-9*10=300-90=210
stim ca: x=3  si y+z=10 , se da factor comun