If x, y and z are integers, what is y - z?
(1) 100^x = (2^y)(5^z)
(2) 10y = (20^x)(5^(z+1))
OA after discussion.
(1) 100^x = (2^y)(5^z)
(2) 10y = (20^x)(5^(z+1))
OA after discussion.
100^x=(4*25)^x=4^x.25^x=2^2x.5^2x=2^y.5^z
Y=2x z=2x y-z=0
1.suff
10y=(20^x)(5^(z+1)
10y=20^x(5.5^z)=4^x.5^x(5.5^z)=4^x5.5^(x+z)
2. not sufficient
imo A
