x + y + z = 6, (1) x - y + z = 2, (2) 2x + y - z = 1. (3) Distract equation (2) from equation (1) (both sides). You ill get 2y = 6-2 = 4 ---> y = 2. Substitute y = 2 into equations (1) and (3). You will get x + z = 4, (4) ( from (1) ) 2x - z = -1. (5) ( from (3) ) Add equations (4) and (5). You will get 3x = 3 ---> x = 1. Now everybody can determine z. From (4), z = 4 - x = 4 - 1 = 3. Answer. x=1, y=2, z=3.
x + y + z = 6 -------- Considering X is same as x ------- eq (i)
x - y + z = 2 -------- Considering X is same as x ------- eq (ii)
2x + y - z = 1 ------- eq (iii)
2y = 4 ------ Subtracting eq (ii) from eq (i)
y =, or 2
3x = 3 ------ Adding eqs (ii) & (iii)
x =, or 1
1 + 2 + z = 6 ------- Substituting 1 for x, and 2 for y in eq (i)
3 + z = 6
z = 6 - 3, or 3
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