\(\left(3x-5\right)\left(4x-7\right)+\left(4-x\right)^2\)
\(12x^2-41x+35+16-8x+x^2\)
\(13x^2-49x+51\)
\(\left(3x-5\right)\left(4x-7\right)+\left(4-x\right)^2\)
\(=12x^2-21x-20x+35+\left(4^2-2.4.x+x^2\right)\)
\(=12x^2-21x-20x+35+16+8x-x^2\)
\(=11x^2-33x+51\)