SOLUTION: I need an intermediate step if this equation is be solved by eliminating one unknown by addition? 5x+5y=1 and 3x-8y=5

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Question 400006: I need an intermediate step if this equation is be solved by eliminating one unknown by addition? 5x+5y=1 and 3x-8y=5
Found 3 solutions by josmiceli, nerdybill, ewatrrr:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
5x+%2B+5y+=+1
3x+-+8y+=+5
There's a few ways you could do it, but I would
multiply the 1st equation by 8, and the 2nd
equation by 5.
40x+%2B+40y+=+8
15x+-+40y+=+25
Now just add the equations
55x+=+33
x+=+3%2F5
Plug this into the 1st
5%2A%283%2F5%29+%2B+5y+=+1
3+%2B+5y+=+1
5y+=+-2
y+=+-%282%2F5%29

Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
5x+5y=1
3x-8y=5
.
Multiply top equation by 8:
40x+40y=8
3x-8y=5
.
Multiply bottom equation by 5 and add equations together:
40x+40y=8
15x-40y=25
-----------
55x = 33
x = 33/55
x = 3/5
.
Substitute above into:
3x-8y=5
3(3/5)-8y=5
9/5-8y=5
9-40y=25
-40y=16
y = -16/40
y = -2/5
.
solution: (x,y) = (3/5, -2/5)



Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

5x + 5y = 1 

3x - 8y = 5



   5x +  5y = 1 

3*5/8x - 5y = 5*5/8  |One intermediate step would be multiplying 2nd Eq by 5/8



5x + 15/8x = 1 + 25/8

     55/8x = 33/8

         x = 3/5

    5x + 5y = 1 

5(3/5) + 5y = 1 

      5y = 1-3

       y = -2/5

CHECKING our Answer***

3x - 8y = 5

 9/5 + 16/5 = 25/5 = 5