Question

if a divide w and w divide k, then a divde k
(z and y is intergers)
proof plz

I got up to
az = w and wy = k
a(zy) = k
and I am stucked here

Answer 1

\[
\frac wa = z; ~~ a = \frac wz \\
\frac kw = y; ~~ k = wy \\
\frac ka = \frac {wy}{w/z} = wy * \frac zw = zy ~~~~~\text {zy is integer because z and y are integers.}
\]

Answer 2

thx

Answer 3

yw.