Verified Answer :

naǫ

\(-2x-y=-9 \\ 5x-2y=18 \\ \\ \hbox{solve the first equation for y:} \\ -2x-y=-9 \ \ \ |+2x \\ -y=-9+2x \ \ \ |\times (-1) \\ y=9-2x \\ \\ \hbox{substitute 9-2x for y in the second equation:} \\ 5x-2(9-2x)=18 \\ 5x-18+4x=18 \\ 9x-18=18 \ \ \ |\div 9 \\ x-2=2 \ \ \ |+2 \\ x=4 \\ \\ y=9-2x=9-2 \times 4=9-8=1 \\ \\ \boxed{(x,y)=(4,1)}\)

-2x-y = -9
5x-2y=18

-solve for y in terms of x
-y= 2x-9
y=-2x+9

substitute
5x-2 ( -2x+9)=18
5x+4x -18=18
9x-18=18
9x= 36
x=4
substitute for x
-2 (4) -y= -9
-8 -y = -9
-y = -1
y= 1
ANSWER x= 4
y=1

hope this helps

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