1)
a.2y(3y3 +4y-18)
=2y.3y3 +2y.4y-2y.18
=6y4 +8y2 -36 y
b.(3y+x)(x-3y)
=(x+3y)(x-3y)=(x+3y)(x−3y)
=x2 -(3y)2
=x2 -9y 2
c.(-4+x)2
=(x-4)
=x2 -8x+16
2)
a.9y3 - 36y2 x
=9y2 x (y-4)
b.64-y2 -x2 +2xy
=82 -(y2 -2xy+x2)
=82 -(y-x)2
=(8-y+x)(8+x-y)
c. x2 +x-30
=x2 +6x-5x-30
=(x2 +6x)-(5x+30)
=x(x+6)-5(x+6)
=(x+6)(x-5)