math help urgent

what di di do wrong in this???

the question is: x-8y=18
-16x+16y=-8

i did :
first multiplied the first equation with 2
then

2x-16y=36
-16+16y=-8
-----------
-14x=28
x=28/-14
x=-2

now

x-8y=18
(-2)-8y=18
-8y=18+2
-8y=20
y=20/-8
y= 2.5

plz help me what did i do wrong??

asked by Anonymous
  1. I can't see anything besides that y=-2.5 because you divide by a negitive

    posted by Sally
  2. oo....ok thanks sally

    posted by Anonymous

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