SOLUTION: Solve the following pair of simultaneous equations. 3/5x - 4y = -1 0.8x - 3.5y = 1/2

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Question 1171053: Solve the following pair of simultaneous equations.
3/5x - 4y = -1
0.8x - 3.5y = 1/2
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

%283%2F5%29x+-+4y+=+-1-> both sides multiply by 5
0.8x+-+3.5y+=+1%2F2-> both sides multiply by 10
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3x+-+20y+=+-5.........eq.1
8x+-+35y+=+5.........eq.2
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start with eq.1
3x+-+20y+=+-5.........eq.1, solve for x
3x=20y++-5
x=20y%2F3++-5%2F3...........eq.1a
substitute in eq.2
8%2820y%2F3++-5%2F3%29+-+35y+=+5.........eq.2, solve for y
160y%2F3++-40%2F3+-+35y+=+5-> both sides multiply by 3
160y++-40+-+105y+=+15
160y-+105y+=+15%2B40
55y+=55
y+=1

go to eq.1a

x=20y%2F3++-5%2F3...........eq.1a, substitute y
x=%2820%2A1%29%2F3++-5%2F3
x=20%2F3++-5%2F3
x=15%2F3
x=5

solutions:x=5,y+=1