Question

57-92=17 -2c-ust +1 8x1322-1) = 677343 (x + 55-22-20 K 54+32--1 5x+363) = -1 5x+aen -6 8+2=6 2:6-8 -44)-5)-(2) 16-3942=12 18-y-18 -x-57-3222 - (-1)-sy-5633=2 2-35-17 = 2 2.3.3 -Byzo yo TARE 3) -x - 5y + z = 17 -5x - 5y +56=5 2x + 5y - 3z=-10 4) 4x + 4y + 2x - 4y+ 5x - 4y

Answer 1

`\begin{gathered} x=4 \\ y=2 \\ z=0 \end{gathered}`

Explanation:

We have the following system of equations:

`\begin{gathered} 4x+4y+z=24\text{ (1)} \\ 2x-4y+z=0\text{ (2)} \\ 5x-4y-5z=12\text{ (3)} \end{gathered}`

We solve by elimination:

`\begin{gathered} \text{ We add (1) and (2)} \\ 4x+4y+z+2x-4y+z=24+0 \\ 6x+2z=24\text{ }\rightarrow x=(24-2z)/(6)\text{ (4)} \\ \text{ We add (1) and (3)} \\ 4x+4y+z+5x-4y-5z=24+12 \\ 9x-4z=36\text{ (5)} \\ \text{ replacing (4) in (5)} \\ 9\cdot((24-2z)/(6))-4z=36 \\ 36-3z-4z=36 \\ -7z=36-36 \\ z=(0)/(-7) \\ z=0 \end{gathered}`

Now, replacing z in (4):

`\begin{gathered} x=(24-2\cdot0)/(6) \\ x=(24)/(6) \\ x=4 \end{gathered}`

Then, replacing z and x in (1):

`\begin{gathered} 4\cdot4+4y+0=24 \\ 16+4y=24 \\ 4y=24-16 \\ y=(8)/(4) \\ y=2 \end{gathered}`