a) \(=5x\left(y+2x\right)\)
b) \(=x\left(x-6y\right)+3\left(x-6y\right)=\left(x-6y\right)\left(x+3\right)\)
c) \(=\left(x^2+6x+9\right)-y^2=\left(x+3\right)^2-y^2=\left(x-y+3\right)\left(x+y+3\right)\)
d) \(=\left(x^2-5x\right)-\left(4x-20\right)=x\left(x-5\right)-4\left(x-5\right)=\left(x-4\right)\left(x-5\right)\)
a) 5x( y+ 2)
b)(x2+3x)-(6xy+ 18y)
=x(x+3)-6y(x+3)
=(x+3)(x-6y)
c)(x2-y2)+ (6x+9)
=(x-y)(x+y)+3(2x+3)
d) chịu nha
a) 5xy+10x=5x(y+2)
b) x2-6xy+3x-18y
=(x2+3x)+(-6xy-18y)
=x(x+3)-6y(x+3)
=(x-6y)(x+3)
c) x2-y2+6x+9
=(x2+6x+9)-y2
=(x+3)2-y2
=(x+3-y)(x+3+y)
d) x2-9x+20
=x2-4x-5x+20
=x(x-4)+5(x-4)
=(x+5)(x-4)