anceer wrote:
What is the value of x ?
(1) 3^x X 5^y = 75
(2) 3^(x-1)(y-2) = 1
Here we are not told whether x is an integer or not.
st.1 3^x.5^y = 75, if x and y both are integers, then x=1 and y=2. but if they are not, then x and y can take any non-integer value. for example say x=0, then we have
5^y=75
y=2.68
st.2 3^(x-1)(y-2)=1
(x-1)(y-2)=0
if x=1 then y can have any value. if y=2 then x can have any value.
hence insufficient
combining st.1 and st.2
we have a common solution of x=1.
hence answer should be C.