Penyelesaian sistem persamaan linear dua variabel 3y-4z=22-y+z dan 5y+z=5+2y-z adalah . . . A. Y= 3 dan z= -2 B. Y= 3 dan z= 2 C. Y= -3 dan z= -2 D. Y= -3 dan z= 2

<p>3y - 4z = 22 -y + z &nbsp;</p><p>3y + y - 4z - z = 22</p><p>4y - 5z = 22 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; ....(1)</p><p>&nbsp;</p><p>5y + z = 5 + 2y - z</p><p>5y - 2y + z + z = 5</p><p>3y + 2z = 5 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; ....(2)</p><p>&nbsp;</p><ul><li><strong>Eliminasi z untuk mendapatkan nilai y</strong></li></ul><p>&nbsp; &nbsp; &nbsp; 4y - 5z = 22 &nbsp;(dikali 2) --&gt; &nbsp; &nbsp; 8y - 10z = 44</p><p>&nbsp; &nbsp; &nbsp; 3y + 2z = 5 &nbsp; &nbsp;(dikali 5) --&gt; <u>15y + 10z = 25&nbsp;</u> +</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 23y &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; = 69</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;y = 69 : 23 = 3</p><ul><li><strong>Substitusikan y = 3 ke persamaan (2)</strong></li></ul><p>&nbsp; &nbsp; &nbsp; 3y + 2z = 5</p><p>&nbsp; &nbsp; &nbsp; 3(3) + 2z = 5</p><p>&nbsp; &nbsp; &nbsp; 9 + 2z = 5</p><p>&nbsp; &nbsp; &nbsp; 2z = 5 - 9</p><p>&nbsp; &nbsp; &nbsp; 2z = -4</p><p>&nbsp; &nbsp; &nbsp; z = -4 : 2 = -2</p><p>&nbsp;</p><p><strong>Jawaban :</strong></p><p>A. y = 3 dan z = -2</p>