\(29\times23-29\times87-71\times64\)
\(=29\times\left(23-87\right)-71\times64\)
\(=29\times\left(-64\right)-\left(-71\right)\times\left(-64\right)\)
\(=\left(-64\right)\times\left(29--71\right)\)
\(=-64\times100=-6400\)
29 x 23 - 29 x87 - 71 x 64
= 29 x ( 23 - 87) - 71 x 64
= - 29 x 64 - 71 x 64
= -64 x ( 29 + 71)
= -64 x 100
= -6400
\(29\times23-29\times87-71\times64\\ =667-2523-4544\\ =-1856-4544\\ =-6400\)