x + 2y + 3z = 73....................(1) 3x + 2y + 10z = 195...............(2) -x - y - z = -31........................(3) You can solve these by elimination:- First add equations (1) and (3) to eliminate x:- y + 2z = 42.......................(4) Now multiply equation (1) by -3:- -3x - 6y - 9z = -219 Now add this to equation (2) this gives:- -4y + z = -24.....................(5) multiply this by -2:- 8y - 2z = 48......................(6) Now add this to equation 4 to eliminate z:- 9y = 90 y = 10
and from equation 4:- 10 + 2z = 42 2z = 32 z = 16
Now to find value of x plug in y = 10 and z = 16 into equation (1):-
