Question

daca x+y=10 si y+2z=12,calculeaza 3x+10z

Answer 1

x+2y+2z=10+12=22/2
x+y+z=11
10+z=11
z=11-10
z=1

y+2z=12
y+2×1=12
y+2=12
y=12-2
y=10

x=10-10
x=0

3x+10z=12
3×0+10×1=0+10=10