nilai x+y=

<p>[x-2 &nbsp; &nbsp;7 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;[-5 &nbsp; &nbsp; &nbsp;7</p><p>&nbsp; &nbsp;1 &nbsp; &nbsp;y+4] &nbsp; &nbsp;= &nbsp; &nbsp; &nbsp; &nbsp;1 &nbsp; &nbsp; &nbsp;-6]<br>&nbsp;</p><p>x-2= -5</p><p>x= -5+2</p><p>x= -3</p><p>&nbsp;</p><p>y+4= -6</p><p>y= -6-4</p><p>y= -10</p><p>&nbsp;</p><p>x+y= -3 + (-10)= -13</p>