You can put this solution on YOUR website! the least common multiple is 245z^8
245 is a multiple of 245 (1*245 = 245) and 245 is a multiple of 35 (7*35 = 245)
z^8 is a multiple z^8 (1*z^8 = z^8) and z^8 is a multiple of z^6 (z^6*z^2 = z^8).
here's a reference that explains the principle in halfway decent fashion. http://www.mathsteacher.com.au/year10/ch11_rational/04_lcm/lcm.htm
using this principle:
your expressions are 35z^6 and 245z^8
break 35z^6 into factors of 5*7*z^6
break 245z^8 into factors of 5*7^2*z^8
the factors in each with the highest exponents associated with them are:
5 and 7^2 and z^8
that makes the least common multiple equal to:
5*49*z^8 = 245z^8.
