SOLUTION: A can of house paint cost 4 dollars more than a can of wall paint. If 7 cans of house paint cost the same as 9 cans of wall paint, find the price of each paint

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Question 1012471: A can of house paint cost 4 dollars more than a can of wall paint. If 7 cans of house paint cost the same as 9 cans of wall paint, find the price of each paint
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = the price of a can of house paint
Let +b+ = the price of a can of wall paint
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(1) +a+=+b+%2B+4+
(2) +7a++=+9b+
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Substitute (1) into (2)
(2) +7%2A%28+b+%2B+4+%29++=+9b+
(2) +7b+%2B+28+=+9b+
(2) +2b+=+28+
(2) +b+=+14+
and
(1) +a+=+b+%2B+4+
(1) +a+=+14+%2B+4+
(1) +a+=+18+
The price of a can of house paint is $18
The price of a can of wall paint is $14
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check:
(2) +7a++=+9b+
(2) +7%2A18++=+9%2A14+
(2) +126+=+126+
OK