[tex]\displaystyle\bf\\1)\\\\(d+2)(d-4)+(d-4)^{2} =d^{2} -4d+2d-8+d^{2}-8d+16=\\\\=2d^{2} -10d+8\\\\\\2)\\\\4(f+4)^{2} -4f^{2}=4\cdot(f^{2} +8f+16)-4f^{2} =4f^{2} +32f+64-4f^{2} =\\\\=32f+64[/tex]