Question

If f(x) = 7 + 4x and g(x)=1/2x, what is the value of (f/g)(5)?

Answer 1

$f(x)=7+4x;\ g(x)=\dfrac{1}{2}x\\\\\left(\dfrac{f}{g}\right)(x)=\dfrac{f(x)}{g(x)}=\dfrac{7+4x}{\frac{1}{2}x}=\dfrac{2(7+4x)}{x}=\dfrac{14+8x}{x}\\\\\left(\dfrac{f}{g}\right)(5)=\dfrac{f(5)}{g(5)}=\dfrac{14+8\cdot5}{5}=\dfrac{14+40}{5}=\dfrac{54}{5}=10.8$

Answer 2

Answer:

$\frac{54}{5}$

Step-by-step explanation:

The meaning of $\left ( \frac{f}{g}\right)(5)$ is $\frac{f(5)}{g(5)}$. So we must find $f(5)$ and $g(5)$ and then make the quocient.

You have $f(x)=7+4x$ and therfore you have to change x by 5 to obtain $f(5)$:

$f(5)=7+4(5)=7+20=27$

Do the same for g(5) with $g(x)=\frac{1}{2}x$

$g(5)=\frac{1}{2}(5)=\frac{5}{2}$

Finally we have

$\left(\frac{f}{g} \right)(5)=\frac{f(5)}{g(5)}=\frac{27}{\frac{5}{2}}=\frac{54}{5}$