Question 1148269
Use the first two equations to find x and y.  Use these results to find z in the last equation.   You see that first two equations do not contain z.


{{{8y=7(y+2)-9}}}
{{{8y=7y+14-9}}}
{{{y=14-9}}}
{{{highlight(y=5)}}}
-
{{{x=y+2}}}
{{{x=5+2}}}
{{{highlight(x=7)}}}
-

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