Question

Gente me ajudem qual e a resposta e o calculo 10=3 (z-2)-(z-18)

Answer 1

$10=3\left(z-2 \right )-\left(z-18 \right )\\ \\ 10=3z-6-z+18\\ \\ 10+6-18=3z-z\\ \\ -2=2z\\ \\ z=\,^{-2}\!\!\!\diagup\!\!_{2}\\ \\ \boxed{z=-1}$

Answer 2

$10 = 3(z - 2) - (z - 18) \\ \\ 10 = 3z - 6 - z + 18 \\ \\ 10 = 2z + 12 \\ \\ -2z = 12 - 10 (-1) \\ \\ 2z = -12+10 \\ \\ 2z = -2 \\ \\ z = -\dfrac{2}{2} \\ \\ => -1$