How do you solve the following system?: 8x -5y =9 , 5x -7y = 28x5y=9,5x7y=2

1 Answer
Mar 23, 2018

Solution: x=53/31, y=29/31x=5331,y=2931

Explanation:

8x-5y=9 ; (1) ; 5x-7y=2 ; (2)8x5y=9;(1);5x7y=2;(2) . Multiplying equation(1)

by 55 and equation(2) by 88 we get,

40x-25y=45 ; (3) ; 40x-56y=16 ; (4)40x25y=45;(3);40x56y=16;(4) Subtracting

equation(4) from equation(3) we get,

31y=29 :. y= 29/31 Putting y= 29/31 in equation (1)

we get 8x-5*29/31=9 or 8x= 9+145/31or 8x= 424/31 or

x= 424/(31*8) = 53/31:. Solution: x=53/31, y=29/31 [Ans]