Answer:
A.
Step-by-step explanation:
y=loga(x) is just the same as x=a^y
- 1/2
turn 2/5 to have the same denominator as 10
2 ( 2 ) = 4
5 ( 2 ) = 10
4/10 - 9/10
= -5/10
simplify
-5/10 = -1/2
hope this helps
