SOLUTION: 0.17x - 0.35y = 7 5x + 7y = 76 answer in decimal form and explain the steps to me please

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Question 183128: 0.17x - 0.35y = 7
5x + 7y = 76 answer in decimal form and explain the steps to me please

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
I'll get it out of decimal form and then put it
back to decimal form at end
(1) .17x+-+.35y+=+7
(2) 5x+%2B+7y+=+76
--------------------------
Multiply both sides of (1) by 100
(1) 17x+-+35y+=+700
(2) 5x+%2B+7y+=+76
Now multiply both sides of (2) by 5
(1) 17x+-+35y+=+700
(2) 25x+%2B+35y+=+380
Now add (2) and (1)
(1) 17x+-+35y+=+700
(2) 25x+%2B+35y+=+380
42x+=+1080
x+=+25.714
Substitute this result back ito (2)
(2) 5x+%2B+7y+=+76
5%2A25.714+%2B+7y+=+76
7y+=+76+-+128.570
7y+=+-52.570
y+=+-7.510
Check answers:
(1) .17x+-+.35y+=+7
(2) 5x+%2B+7y+=+76
-------------------------
(1) .17%2A25.714+-+.35%2A%28-7.51%29+=+7
(1) 4.371+%2B+2.629+=+7
(1) 6.9995+=+7 close enough
(2) 5x+%2B+7y+=+76
(2) 5%2A25.714+%2B+7%2A%28-7.51%29+=+76
(2) 128.57+-+52.57+=+76
(2) 76+=+76
OK