Here is the equation:
[tex]f(x)=4x+1[/tex]
You need to find f(3). To do that, substitute all the x's with 3:
[tex]f(x)=4x+1 \rightarrow f(3)=4\times3 + 1[/tex]
The first thing you need to do is multiply 4 by 3. Multiply:
[tex]4 \times 3 = 12[/tex]
Here is your new equation:
[tex]f(3)=12+1[/tex]
To get your answer, you need to add 12 and 1. Add:
[tex]12+1 = 13[/tex]
That means:
[tex]\bf f(3)=13[/tex]
If you have any questions, feel free to ask in the comments! :)
