Respuesta :

Hrishii

Step-by-step explanation:

[tex]f(x) = - 3 {x}^{2} + 4x - 12 \\ \\ \therefore \: f(3x) = - 3 ({3x})^{2} + 4(3x) - 12 \\ \therefore \: f(3x) = - 3 \times 9 {x}^{2} + 4 \times 3x- 12 \\ \therefore \: f(3x) = - 27 {x}^{2} + 12x- 12 [/tex]