SOLUTION: How do you do this system of equation: 3x+5y=56 y= 66-8y / 5

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Question 109479: How do you do this system of equation:
3x+5y=56
y= 66-8y / 5

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!


3x%2B5y=56
y=+66-8y+%2F+5…..I guess, here should be 8x, not 8y
3x%2B5y=56
y=+66-8x+%2F+5…..you can solve this for y and substitute this y value in first equation and find out what is x equal to

3x+%2B+5+%28%2866-8x%29+%2F+5%29+=+56……here we can cancel 5
3x+%2B++66+-+8x++=+56……
-+5x+%2B+66++=+56……move -5x to the right, and 56 to the left

+66+-+56+=+5x……
+10++=+5x……divide both sides by 5
x+=+2
Now find y
3x%2B5y=56
3%2A2%2B5y=56
5y=56+-+6
5y=50…….. divide both sides by 5
y+=+10


2. in case you did write your second equation correctly, you will do it this way
3x+%2B+5y+=+56
y+=+66+-+8y+%2F+5…..solve for y
y=+66+-+8y+%2F+5…..multiply both sides by 5
5y+=+66%2A5+%96+%288y%29%2F5%2A5
5y+=+330+%96+8y…move -8y to the left
5y+%2B+8y+=+330
13y+=+330
y+=+330%2F13
y+=+25.38……..substitute this in first equation and find x

3x+%2B+5y+=+56……..move 5y to the right
3x+=+-5y+%2B+56
3x+=+-5%2825.38%29+%2B+56
3x+=+-126.9%2B+56
3x+=+-70.9
x+=+-70.9%2F3
x+=+-23.63