Bantu jawab dong

<p><strong>Dik</strong>:</p><p>f(x) = ax+b</p><p>f(2) = 4<br>f(5) = 13</p><p><strong>Dit</strong>: f(8)-f(3)</p><p><strong>Penyelesaian:</strong></p><ol><li><strong>Selesaikan a &amp; b</strong></li></ol><p>f(2) = 4</p><p>f(2) = a(2)+b = 4</p><p>2a+b = 4 ...(i)</p><p>f(5) = 13</p><p>f(5) = a(5)+b=13</p><p>5a+b = 13 ... (ii)</p><ul><li>Eliminasi b pada persamaan (i) &amp; (ii)</li></ul><p>2a+b = 4</p><p><u>5a+b = 13 &nbsp;</u> -</p><p>-3a &nbsp; &nbsp;= -9</p><p>a = -9/-3</p><p>a = 3</p><ul><li>Substitusi a ke persamaan (i)</li></ul><p>2(3)+b = 4</p><p>6+b = 4</p><p>b = -6+4</p><p>b = -2</p><p>2. <strong>Substitusi a &amp; b ke f(8) &amp; f(3)</strong></p><p>f(8) = 3(8)+(-2)</p><p>= 24-2</p><p>= 22</p><p>f(3) = 3(3) +(-2)</p><p>= &nbsp;9-2</p><p>= 7</p><p>&nbsp;</p><p>Jadi,</p><p>f(8) - f(3)</p><p>= 22-7</p><p>= 15</p><p><strong>Jawabannya</strong></p><p><strong>C. 15</strong></p>