The solution of the system of equations $2x +\frac{1}{2}y-z=1,2y= 3, x+2z = 4$ is:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → $x= 0.9, y = 1.5, z = 1.55$
Given system:
$2x + \frac{1}{2}y - z = 1$
$2y = 3$
$x + 2z = 4$
From $2y = 3$:
$y = \frac{3}{2}$
Use $x + 2z = 4$ → $x = 4 - 2z$
Substitute into first equation:
$2(4 - 2z) + \frac{1}{2}\left(\frac{3}{2}\right) - z = 1$
$8 - 4z + \frac{3}{4} - z = 1$
$8.75 - 5z = 1$
$-5z = -7.75$
$z = \frac{7.75}{5} = \frac{31}{20}$
Now compute $x$:
$x = 4 - 2\left(\frac{31}{20}\right)$
$x = 4 - \frac{62}{20}$
$x = \frac{80}{20} - \frac{62}{20}$
$x = \frac{18}{20} = \frac{9}{10}$
The solution is: $x = \frac{9}{10},\; y = \frac{3}{2},\; z = \frac{31}{20}$.