tolong bantu

<p>Jawaban yang tepat adalah &nbsp;<strong>-5</strong></p><p>&nbsp;</p><p>Pembahasan :</p><p>x + 8 = 2(y + 3)</p><p>x + 8 = 2y + 6</p><p>x = &nbsp;2y + 6 - 8</p><p>x = 2y - 2 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; (1)</p><p>&nbsp;</p><p>x - 4y = 4(x - 2y + 2)</p><p>x - 4y = 4x - 8y + 8</p><p>x - 4x - 4y + 8y = 8</p><p>-3x + 4y = 8 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;(2)</p><p>Substitusikan persamaan (1) &nbsp;ke Persamaan (2)</p><p>-3x + 4y = 8 &nbsp;&nbsp;</p><p>-3(2y - 2) + 4y = 8 &nbsp;&nbsp;</p><p>-6y + 6 + 4y = 8</p><p>-2y = 8 - 6</p><p>-2y = &nbsp;2</p><p>y = 2 : (-2)</p><p>y = -1</p><p>&nbsp;</p><p>Substitusikan y = -1 ke persamaan (1)</p><p>x = 2y - 2&nbsp;</p><p>x = 2(-1) - 2&nbsp;</p><p>x = -2 - 2</p><p>x = -4</p><p>Nilai 2x - 3y = 2(-4) - 3(-1)</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= -8 + 3</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= -5</p><p>Jadi, nilai 2x - 3y adalah <strong>-5</strong></p><p>&nbsp;</p>