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E = ( 2 - x)² + ( 2 - x) ( 9 + x )
= ( 2 - x ) ( 2 - x + 9 + x)
= ( 2 - x ) ( 11)
F = ( ( 3 - 2 x ) ( 5 + x) - ( 5 + x )²
= ( 5 + x) ( 3 - 2 x - 5 - x)
= ( 5 + x ) ( - 3 x - 2)
G = - (15 - x)² - ( 15 - x ) ( 3 - x)
= - ( 15 - x ) ( 15 - x - 3 x+ x)
= - ( 15 - x ) ( - 3 x + 15)