tolong banget

<p>Jawaban &nbsp;<strong>B. 4</strong></p><p>&nbsp;</p><p><strong>Pembahasan&nbsp;</strong></p><p>xz + yz = 4</p><p>&lt;=&gt; z(x + y) = 4</p><p>&lt;=&gt; z.z = 4</p><p>&lt;=&gt; z = 2 atau z = -2</p><p>&nbsp;</p><p>x + y + z = (x + y) + z</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; = z + z</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; = 2 + 2</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; = 4</p><p>&nbsp;</p><p>Jika z = -2, tidak ada opsi jawaban -4</p><p>&nbsp;</p>