Question

2×=z ×+y=6 y+z=7 me ajudem pfv e PR amanhã

Answer 1

2x=z
x+y=6 > y=6-x
y+z=7 (substitui as incógnitas)

(6-x) + (2x) = 7
-x+2x=7-6
x=1

2x=z
2(1) = z
2=z

y=6-x
y= 6-(1)
y=5