SOLUTION: Solve: 2x+2y= -4 x-2y=1 a)(-6, -1) b) (-1, -1) c) (0,-2) d) no solution. *i thought it was B but i checked, and also got C! :[ Three times the sum of a number and 17

Algebra ->  Equations -> SOLUTION: Solve: 2x+2y= -4 x-2y=1 a)(-6, -1) b) (-1, -1) c) (0,-2) d) no solution. *i thought it was B but i checked, and also got C! :[ Three times the sum of a number and 17      Log On


   

Question 697051: Solve: 2x+2y= -4
x-2y=1
a)(-6, -1) b) (-1, -1) c) (0,-2) d) no solution.
*i thought it was B but i checked, and also got C! :[
Three times the sum of a number and 17 is at least 114. Let x represent the number and find all possible values for the number
a)x _> 55 b) x <_ 21 c) x <_ 55 d) x_> 21
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+2x+%2B+2y+=+-4+
Divide both sides by +2+
(1) +x+%2B+y+=+-2+
and
+x+-+2y+=+1+
(2) +x+=+2y+%2B+1+
Plug this into (1)
(1) +2y+%2B+1+%2B+y+=+-2+
(1) +3y+=+-3+
(1) +y+=+-1+
and
+x+-+2y+=+1+
+x+-+2%2A%28-1%29+=+1+
+x+=+-2+%2B+1+
+x+=+-1+
------------
Answer is b) (-1,-1 )
If I try c) ( 0,-2),
------------
(1) +x+%2B+y+=+-2+
(1) +0+%2B%28-2%29+=+-2+
(1) +-2+=+-2+
and
(2) +x+=+2y+%2B+1+
(2) +0+=+2%2A%28-2%29+%2B+1+
(2) +0+=+-3+
So, c) does not work