Question

Answer 1

b.\(4x\left(x-2y\right)+12y\left(2y-x\right)\)

\(=4x\left(x-2y\right)-12y\left(x-2y\right)\)

\(=\left(4x+12y\right)\left(x-2y\right)\)

\(=4\left(x+3y\right)\left(x-2y\right)\)

Answer 2

c)\(4x\left(x+1\right)^2-5x^2\left(x+1\right)-4\left(x+1\right)\)

\(=4x\left(x+1\right)\left(x+1\right)-5x^2\left(x+1\right)-4\left(x+1\right)\)

\(=\left(4x^2+4x\right)\left(x+1\right)-5x^2\left(x+1\right)-4\left(x+1\right)\)

\(=\left(x+1\right)\left(4x^2+4x-5x^2-4\right)\)

\(=\left(x+1\right)\left(-x^2+4x-4\right)\)

\(=\left(x+1\right)[-\left(x^2-4x+4\right)]\)

\(=-\left(x+1\right)\left(x-2\right)\)