SOLUTION: solve by subtitution: 1/5x + 1/2y = 8 x +y = 20 solve by subtitution: 6x + 5y = -3 -x - 5/6y = -7

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Question 162175: solve by subtitution:
1/5x + 1/2y = 8
x +y = 20
solve by subtitution:
6x + 5y = -3
-x - 5/6y = -7
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
1/5x+1/2y=8
x+y=20 or x=20-y
(20-y)/5+y/2=8
[2(20-y)+5y)]/10=8
(40-2y+5y)/10=8
40+3y=10*8
40+3y=80
3y=80-40
3y=40
y=40/3 answer.
x+40/3=20
x=20-40/3
x=(3*20-40)/3
x=(60-40)/3
x=20/3 answer.
Proof:
(20/3)/5+(40/3)/2=8
20/3*1/5+40/3*1/2=8
20/15+40/6=8
1.333+6.667=8
8=8