<p>how do you do this?</p>
<p>Consider the functions f (x) = sqrt x and g(x) = 7x + b. In
the standard (x,y) coordinate plane, y = f (g(x)) passes
through (4,6). What is the value of b ?</p>
<p>f(g(x)) = sqrt(g(x)) = sqrt(7x + b)</p>
<p>So, the equation is just :</p>
<p>y = sqrt(7x + b) and it passes through 4,6.</p>
<p>x = 4, y = 6</p>
<p>6 = sqrt (7*4 + b)</p>
<p>6 = sqrt(28+b)</p>
<p>36 = 28+b</p>
<p>8 = b</p>
<p>of course. I don’t know why I got stuck. thx</p>