Question

x-2y=5z=7
3y+2z=1
4z=8

Answer 1

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Ola Marcia

x - 2y + 5z = 7
3y + 2z = 1
4z = 8

z = 8/4 = 2

3y + 4 = 1
3y = -3
y = -1

x - 2y + 5z = 7
x + 2 + 10 = 7
x = .-5 

pronto