Question 215257
xy+xz + wy+wz
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x(y+z) + w(y+z),,,,,This  is  often  hard  to  see,,think  of  (y+z) =c,,,,then xc+wc = c(x+w),,,and  subst  back,,,(y+z)(x+w)
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(x+w) *(y+z)
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check,,,FOIL  answer,,,xy +xz+wy +wz,,,,ok
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This  is  called  " grouping" factoring
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