Question

I have one question that I really need help with, please help me!!!

If you were to use the substitution method to solve the following system, choose the new system of equations that would result if x was isolated in the first equation.

x – 6y + 3z = 0
2x – 5y + 8z = 7
x + 7y – 4z = 13

Answer 1

Solve the last two equations for y and z to
obtain
\[
\begin{array}{cc}
y=\frac{1}{9} (33-4 x) &\\
z=\frac{19}{6}-\frac{19 x}{36}
\end{array}

\]

Answer 2

Replace y and z by their values in equation 1 to obtain
\[-\frac{2}{3} (33-4 x)+3
\left(\frac{19}{6}-\frac{19
x}{36}\right)+x=0\\

\]
After simplification, you get

\[
x=6
\]

Answer 3

The new set of equations will be
\[
x=6\\
\begin{array}{cc}
y=\frac{1}{9} (33-4 x) &\\
z=\frac{19}{6}-\frac{19 x}{36}
\end{array}

\]