a. x2 - 2x
⇔ x(x - 2)
b. 3x - 6y
⇔ 3(x - 2y)
c. 5(x + 3y) - 15x(x + 3y)
⇔ (5 - 15x)(x + 3y)
d. 3(x - y) - 5x(y - x)
⇔ 3(x - y) + 5x(x - y)
⇔ (3 + 5x)(x - y)
2B:
a: \(\left(x+1\right)^2-\left(x+1\right)=x\left(x+1\right)\)
b: \(x\left(x+y\right)^2+xy\left(x+y\right)=x\left(x+y\right)\left(x+2y\right)\)
c: \(xy\left(x-y\right)-2x+2y=\left(x-y\right)\left(xy-2\right)\)
d: \(y\left(x-y\right)^2+x\left(y-x\right)^2=\left(x-y\right)^2\cdot\left(x+y\right)\)