If we add the last two equations we get
[tex]5x+3y=11[/tex]
If we add the first and the last equations we get
[tex]3x+7y=17[/tex]
Solving these two equations simultaneously you will get
x=1 and y=2
Putting these two values back into any of the equations given (i will use the third equation in this case), we get
[tex]1+2(4)+z=1+8+z=9+z=12[/tex]
Therefore
[tex]z=12-9=3[/tex]
So x=1, y=2 and z=3.
If you need more help with quadratic equations please send me a comment. I can send you a link to help you.
Please mark me as brainliest.
