Exam 4: Systems of Equations

Solve the system by substitution. If the system is inconsistent and has no solution, state this. If the system is dependent, write the form of the solution for any real number $x$ . - $y=6 x+40$ $7 x+5 y=-59$

x+y+z =-2 X-y+4z =-14 3x+y+z =-8

Solve the system of four equations in four unknowns using matrices. - $\mathrm{w}+3 \mathrm{x}+\mathrm{y}-2 \mathrm{z}=-10$ $-3 \mathrm{w}-\mathrm{x}+3 \mathrm{y}+\mathrm{z}=5$ $2 \mathrm{w}+3 \mathrm{x}-\mathrm{y}+3 \mathrm{z}=7$ $-\mathrm{w}+\mathrm{x}+\mathrm{y}-3 \mathrm{z}=-7$

Graph the system of inequalities. - $x - y \leq -1$ $x + 2y ? 8$ $Y \leq 7$