SOLUTION: as written on my homework = solve the system : 4x-7/2y=-18 7/2x-3y=-31/2

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Question 181450This question is from textbook Algebra & trigonometry blitzer
: as written on my homework =
solve the system :
4x-7/2y=-18
7/2x-3y=-31/2 This question is from textbook Algebra & trigonometry blitzer

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
(1) 4x+-+%287%2F2%29y+=+-18
(2) %287%2F2%29x+-+3y+=+-%2831%2F2%29
Multiply both sides of (2) by 8%2F7
(2) %288%2F7%29%287%2F2%29%2Ax+-+%288%2F7%29%2A3y+=+-%288%2F7%29%2831%2F2%29
(2) 4x+-+%2824%2F7%29y+=+-%28124%2F7%29
Subtract (1) from (2)
(2) 4x+-+%2824%2F7%29y+=+-%28124%2F7%29
(1) -4x+%2B+%287%2F2%29y+=+126%2F7
%2849%2F14+-+48%2F14%29%2Ay+=+2%2F7
%281%2F14%29%2Ay+=+2%2F7
y+=+4
Plug this back into (1)
(1) 4x+-+%287%2F2%29y+=+-18
(1) 4x+-+%287%2F2%29%2A4+=+-18
4x+=+-18+%2B+14
4x+=+-4
x+=+-1
The solutions are x+=+-1 and y+=+4