№7.
а)30a^2/12ab = 5a/2b
б)12xz/16xyz = 3/4y
в)18xyz/24yz = 3x/4
г)12cd/15dc = 4/5
д)46mnk^2/23n^2kt = 2mk/nt
е)54cd^3/18c^3d = 3d^2/c^2
ж)9ab^2/36a^2bc = b/4ac
з)45ac/54abk = 5c/6bk
и)125k^3z/350kz^3 = 5k^2/14z^2
к)45a^3b^2x/135a^2b^3x = a/3b
№8.
a)(xy-xz)/(yd-zd) = x(y-z)/d(y-z) = x/d
б)(ab-ac)/(b-c) = a(b-c)/(b-c) = a
в)(a^2-3a)/2a(a-3) = a(a-3)/2a(a-3) = 1/2
г)(2a-6b)/(5a-15b) = 2(a-3b)/5(a-3b) = 2/5
д)(5a-5b)/10 = 5(a-b)/10 = (a-b)/2
е)(at+ak)/(bt+bk) = a(t+k)/b(t+k) = a/b