Question

Найти значение выражения при указанных значениях переменно x=5$frac{17}{29}$
(x-3)(x+4)-(x+6)(x-5)
Надо срочно.

Answer 1

(x-3)(x+4)-(x+6)(x-5)= x²+4x-3x-12-x²+5x-6x+30= 18

Answer 2

$(5 frac{17}{29} - 3)(5 frac{17}{29} + 4) - (5 frac{17}{29} + 6)(5 frac{17}{29} - 5) = \ = ( frac{162}{29} - 3)( frac{162}{29} + 4) - ( frac{162}{29} + 6)( frac{162}{29} - 5) = \ = ( frac{162 - 3 times 29}{29} )( frac{162 + 4 times 29}{29} ) - ( frac{162 + 6 times 29}{29} )( frac{162 - 5 times 29}{29} ) = \ = ( frac{162 - 87}{29} )( frac{162 + 116}{29} ) - ( frac{162 +174 }{29} )( frac{162 - 145}{29} ) = \ = frac{75}{29} times frac{278}{29} - frac{336}{29} times frac{17}{29} = \ = frac{20850}{841} - frac{5712}{841} = frac{15138}{841} = 18$