Question

If y(x) = 3(x+5) +4/x, what is f(a+ 2)?

Answer 1

Answer:

Step-by-step explanation:

Theyre basically telling you that x = (a + 2)

All you have to do is replace x with a + 2

$f(a+2)=3(a+2+5)+\frac{4}{a+2}$

Next you have to simplify, 2+5 = 7 to get 3(a+7). Apply the distributive property to get 3a + 21. Your new equation is now:

$f(a+2)=(3a+21)+\frac{4}{a+2}$

Now here's the issue, you cant add those two terms yet because we need a common denominator. Multiply the numerator and denominator of 3a + 21 by a+2 to get:

$=\frac{(a+2)(3a+21)}{a+2} +\frac{4}{a+2}$

You gotta now apply FOIL to get:

$\frac{3a^2+27a+42}{a+2} +\frac{4}{a+2} = \frac{3a^2+27a+46}{a+2}$

There is your answer