<p>Let the function g be defined by g(x) = 2x-3. If g(k) = g(2k-3), what is the value of g(4k). Answer is 21 but I don't know how to get it.</p>
<p>okay so you know that g(k) = g(2k-3)... so solve for k.</p>
<p>g(k) = 2k-3
g(2k-3) = 2(2k-3) -3 ... since (2k-3) becomes the x value</p>
<p>now set the two equal to each other...</p>
<p>2k-3 = 4k-9
k =3</p>
<p>so... g(4k) = g(12)
g(12) = 2(12)-3
g(12) = 21</p>
<p>get it?</p>