Answer:
[tex]m(x) = 3( {x}^{2} + 5) + 61 \\m(12) = 3( {12}^{2} + 5) + 61 \\ = 3(144 + 5) + 61 \\ = 3(149) + 61 \\ = 447 + 61 \\ = 508 [/tex]