Given the below expression;
[tex]8+s^2(t+4-4r)[/tex]We're asked to evaluate for r = 4, s = -4 and t = 6, all we need to do is substitute the given values of r, s and t into the expression above;
[tex]\begin{gathered} 8+(-4)^2\lbrack(6)+4-4(4)\rbrack \\ \end{gathered}[/tex]Let's go ahead and clear the brackets and solve;
[tex]\begin{gathered} 8+16(-6) \\ =8-96 \\ =-88 \end{gathered}[/tex]Therefore, our answer is -88.