SOLUTION: .5x + y = 9 1.6x + 0.2y = 13 to solve this equation, use subsitution

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Question 946957: .5x + y = 9
1.6x + 0.2y = 13
to solve this equation, use subsitution
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

.5x+%2B+y+=+9+..........eq.
1.6x+%2B+0.2y+=+13......eq.2
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.5x+%2B+y+=+9+ solve for y
+y+=+9-.5x+....substitute in eq.2

1.6x+%2B+0.2%289-.5x%29+=+13......eq.2 solve for x
1.6x+%2B+1.8-0.1x+=+13
1.6x-0.1x+=+13-1.8
1.5x+=+11.2...multiply by 10
15x+=+112
x+=+112%2F15
x+=+7.466666666666667
x+=+7.5
go to +y+=+9-.5x+, substitute 7.5 for x and solve for y
+y+=+9-.5%2A7.5+
+y+=+9-3.75+
+y+=+5.25+