Answer
$9x+12y+3z=0 \\ -2x+18y+5z+2w=10 \\ x+7y-8z=-4\\3x+2z=-10$
Work Step by Step
In order to write a matrix that will solve a linear equation, we will write the coefficients of each variable in their own column. Each entry in the matrix shows the coefficient of the variables of the system of equations. Therefore, we reverse the process to compute:
$9x+12y+3z=0 \\ -2x+18y+5z+2w=10 \\ x+7y-8z=-4\\3x+2z=-10$