Question

Check whether z = 6 is the solution of the equation:
5z-2/4 = 7z/6


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Answer 1

Given equations

2x+3y−z=6 →(1)

x−y+7z=8 →(2)

3x−y+2z=7 →(3)

(1)+3×(2)

2x+3y−z+3x−3y+21z=6+24

5x+20z=30

x+4z=6 →(4)

(3)−(2)

2x−5z=−1 →(5)

2×(4)−(5)

2x+8z−2x+5z=12=1

13z=13

z=1

x=6−4z

x=2

⇒ 2(2)+3y−1=6

y=1

∴ x=2,y=1,z=1 is solution of given equations.