SOLUTION: substitute 3.4x+1.3y=15.2 1.7x-0.3x=11.4

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Question 1097851: substitute
3.4x+1.3y=15.2
1.7x-0.3x=11.4
Found 2 solutions by greenestamps, MathTherapy:
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!

I will assume the second equation is supposed to show -0.3y instead of -0.3x....

Are you sure you are supposed to use substitution for this? It is very well suited for solving by elimination; multiplying the second equation by 2 makes it easy.

3.4x+%2B+1.3y+=+15.2
3.4x+-+0.6y+=+22.8
1.9y+=+-7.6
y+=+-4
1.7x+-+0.3%28-4%29+=+11.4
1.7x+-+1.2+=+11.4
1.7x+%3C=+12.6
x+=+8

If I were told that I had to solve this using substitution, then, since 3.4 is twice 1.7, I would solve the second equation for 1.7x (there is nothing in the substitution process that says you have to solve for "x" or "y" by itself):

1.7x-0.3y+=+11.4
1.7x+=+0.3y%2B11.4

Then

3.4x%2B1.3y=15.2
2%280.3y%2B11.4%29%2B1.3y+=+15.2
0.6y%2B22.8%2B1.3y+=+15.2
1.9y+=+-7.6
y+=+-4
1.7x-0.3%284%29+=+11.4
1.7x-1.2+=+11.4
1.7x+=+12.6
x+=+8

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

substitute
3.4x+1.3y=15.2
1.7x-0.3x=11.4
Correct answer: highlight_green%28matrix%282%2C3%2C+x%2C+%22=%22%2C+6%2C+y%2C+%22=%22%2C+-+4%29%29

IGNORE anyone who says otherwise!