g) 2a²c² - 2abc + bd - acd
= 2ac ( ac - b ) - d ( ac - b )
= ( 2ac - d ) ( ac - b )
j) ax² - 5x² - ax + 5x + a - 5
= x² ( a - 5 ) - x ( a - 5 ) + ( a - 5 )
= ( x² - x + 1 ) ( a - 5 )
k) x² + 4xy - 2x - 8y
= x ( x + 4y ) - 2 ( x + 4y )
= ( x - 2 ) ( x + 4y )
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