1.
2. 42wa+54wt+56ha+72ht
=6w(7a+9t) + 8h(7a+9t)
=(6w+8h)(7a+9t)
3. 36yu-72yr+12ou-24ro
=36y(u-2r) + 12o(u-2r)
=(36y+12o)(u-2r)
4. 72he+16we+27hn+6wn
=8e(9h+2w) + 3n(9h+2w)
=(8e+3n)(9h+2w)
5. 26wr-91or-10wd+35od
=13r(2w-7o)+ -5d(2w-7o)
=(13r-5d)(2w-7o)