MATHZ (F.3) 4Q before 6 p.m

(b-4)(b+2)-27
= b2-2b-8-27
= b2-2b-35
= (b-7)(b+5)

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(4y-3)(2y-1)-4(5y-6)
= 8y2-10y+3-20y+24
= 8y2-30y+27
= (4y-9)(2y-3)

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(5x +4y)(5x-4y)-( x+2y)2
= 25x2-16y2-x2-4xy-4y2
= 24x2-4xy-20y2
= 6(6x2-xy-5y2)
= 4(6x+5y)(x-y)

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x2+x+2/9
=(x+1/3)(x+2/3)

Alternative method:
x2+x+2/9
= (1/9)(9x2+9x+2)
= (1/9)(3x+1)(3x+2)
=