Question

x+y =30 y+z=38 x+z 32

Answer 1

x+y=30=> y=30-x=>y=30-12=18
30-x+z=38
 x+z=32=>z=32-x
30-x+32-x=38
-2x+62=38
2(-x+31)=38
-x+31=19
x-31=-19
x=31-19=12 
x+z=32=>12+z=32=>z=20
rezultatul e urmatorul 
x=12
y=18
z=20