( X - 5 )*( 2X + 3 ) - ( X + 4 )*( 4 - X ) = 2X + 5
2X^2 + 3X - 10X - 15 - ( 16 - X^2 ) = 2X + 5
2X^2 - 7X - 15 - 16 + X^2 = 2X + 5
3X^2 - 7X - 31 = 2X + 5
3X^2 - 7X - 2X - 31 - 5 = 0
3X^2 - 9X - 36 = 0
3 * ( X^2 - 3X - 12 ) = 0
ОТВЕТ X^2 - 3X - 12 = 0
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