Use a graphing calculator to Express solutions with approximations to the nearest thousandth.
-$$\begin{array} { l }
- 2 x + 8 y - z = - 15 \
x - 2 y + 7 z = 68 \
- 4 x + y + z = - 18
\end{array}$$
A) $\varnothing$
B) $\{ ( - 7,1,14 ) \}$
C) $\{ ( 7,9,1 ) \}$
D) $\{ ( 7,1,9 ) \}$

Question

Use a graphing calculator to Express solutions with approximations to the nearest thousandth.
-$$\begin{array} { l } 
- 2 x + 8 y - z = - 15 \
x - 2 y + 7 z = 68 \
- 4 x + y + z = - 18
\end{array}$$
A) $\varnothing$
B) $\{ ( - 7,1,14 ) \}$
C) $\{ ( 7,9,1 ) \}$
D) $\{ ( 7,1,9 ) \}$

Quizplus · Accepted Answer

Using a graphing calculator to solve the system of equations, the solution is approximately $x = 7$, $y = 1$, and $z = 9$, which corresponds to choice D.

Use a Graphing Calculator to Express Solutions with Approximations to the Nearest