Answer: A
To write a formula for the composite function [tex]f(g(x))[/tex], put the formula for g into the formula for f.
[tex]y=\sqrt{7x+b}[/tex]
This function is to pass through the point (4, 6), meaning when x = 4, y = 6. Substitute these values to get
[tex]6=\sqrt{7(4)+b} \\ 6=\sqrt{28+b}[/tex]
Square both sides of the equation.
[tex]36=28+b \\ 8=b[/tex]