Question

Given f(x)= 3x+21. A. F(4)=B. F(X)= 50, X=2. C. F(-5)=D. F(X)= -34, X=

Answer 1

The given function is

$f(x)=3x+2$

A . f(4) means we have to evaluate the function when x = 4.

$f(4)=3(4)+2=12+2=14$

Therefore, f(4) = 14.

B. f(x) = 50 means we have to evaluate the function when y = 50.-

$\begin{gathered} 50=3x+2 \\ 50-2=3x \\ x=\frac{48}{3} \\ x=16 \end{gathered}$

Therefore, f(16) = 50.

C. f(-5) means we have to evaluate the function when x = -5.

$f(-5)=3(-5)+2=-15+2=-13$

Therefore, f(-5) = -13.

D. f(x) = -34.

$\begin{gathered} -34=3x+2 \\ -34-2=3x \\ x=\frac{-36}{3} \\ x=-12 \end{gathered}$

Therefore f(-12) = -34.