What is k(-4) equal to?
K:m => 7+m^2
K(-4) = [1]

The function is defined as
[tex]k:m\mapsto m^2+7[/tex]
This means that, taken an input m, the output is the input squared, plus 7.
So, if we take the input -4, we square it to get 16, and we add 7 to get 23.