Question

If \[g\left( x \right)=4x-2\], then how do you find \[g\left( 5 \right)\]?

Answer 1

Hint: From the question given, we have been asked to find \[g\left( 5 \right)\]. We can clearly observe that it can be solved by simple substitution. By using substitution, the given question can be solved very easily.

Complete step by step answer:
From the question, it had been given that \[g\left( x \right)=4x-2\]
The above equation explains that, if we put any value of \[x\] in the left-hand side of the equation, then we have to substitute that value in the right-hand side of the equation.
After substituting the value in the right-hand side of the equation, you have to simplify it further to get the value of \[x\].
From the question, we have been asked to find \[g\left( 5 \right)\].
We already have \[g\left( x \right)=4x-2\].
So, to find \[g\left( 5 \right)\], as we have already discussed above, substitute \[5\] in the right hand side of the equation and simplify further more.
\[g\left( x \right)=4x-2\]
\[\Rightarrow g\left( 5 \right)=4\left( 5 \right)-2\]
As we have already discussed above, simplify further more to get the final answer.
\[\begin{align}
  & g\left( 5 \right)=20-2 \\
 & \Rightarrow g\left( 5 \right)=18 \\
\end{align}\]
As we have already discussed above, we got the value of \[g\left( 5 \right)=18\], by simply substituting.
Therefore, we got the value of \[g\left( 5 \right)=18\].

Note:
 We should be well aware of the functions also we should be well aware of the properties of functions. We should know well about the substitution method clearly to solve the given question. Also, we should do the calculation very carefully after doing the substitution. We should have more practice on these types of problems to get the solution very quickly. This is a very simple question and fewer mistakes are possible in this type of question. Similarly we can answer $ f\left( x \right)=3x $ then $ f\left( 8 \right)=24 $ .