a. \(x^2+6x-y^2+9=\left(x+3\right)^2-y^2=\left(x+3-y\right)\left(x+3+y\right)\)
b. \(2x^2-4x+2=2\left(x^2-2x+1\right)=2\left(x-1\right)^2\)
c. \(2xy+3z+6y+xz=2xy+6y+3z+xz=2y\left(x+3\right)+z\left(3+x\right)=\left(2y+z\right)\left(x+3\right)\)
a,\(x^2+6x-y^2+9\)
\(\Rightarrow\left(x^2+6x+9\right)-y^2\)
\(\Rightarrow\left(x+3\right)^2-y^2\)
c,2xy+3z+6y+xz
\(\Leftrightarrow\left(2xy+xz\right)+\left(3z+6y\right)\)
\(\Leftrightarrow x\left(2y+z\right)+3\left(z+2y\right)\)
\(\Leftrightarrow x\left(2y+z\right)-3\left(2y+z\right)\)
\(\Leftrightarrow\left(2y+z\right)-\left(x-3\right)\)
a.x2+6x-y2+9
=x2+6x+9-y2
=(x+3)2-y2
=(x+3-y)(x+3+y)
b.2x2-4x+2
=2(x2-2x+1)
=2(x-1)2
c.2xy+3z+6y+xz
=2xy+6y+3z+xz
=2y(x+3)+z(3+x)
=(x+3)(2y+z)
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