\(E=\left(4-x\right)\left(x+4\right)-\left(x+2\right)^2\)
\(E=4x+16-x^2-4x-x^2-4x-4\)
\(E=-2x^2-4x+12\)
\(P=\left(2x+3\right)^2-\left(2x+1\right)\left(2x-1\right)\)
\(P=4x^2+12x+9-4x^2-1\)
\(P=12x+10\)
\(Q=\left(4-3x\right)^2-\left(9x-1\right)\left(9x+1\right)\)
\(Q=16-24x+9x^2-81x^2+1\)
\(Q=17-24x-74x^2\)
\(M=\left(5+x\right)\left(x-5\right)-\left(x-3\right)^2\)
\(M=5x-25+x^2-5x-x^2+6x-9\)
\(M=-34+6x\)
\(N=2\left(3x+1\right)\left(x-2\right)-6\left(x+2\right)^2\)
\(N=\left(6x+2\right)\left(x-2\right)-\left(6x+12\right)^2\)
\(N=6x^2-12x+2x-4-36x^2-144x-144\)
\(N=-30x^2-154x-148\)