Algebra-1

Question Analysis
This question tests the student's ability to find the first term of a geometric sequence given two non-adjacent terms.

Key Concept Explanation
The common ratio can be found by setting up a ratio between the 5th term and the 3rd term, then solving for . Once is known, the first term can be calculated using the relationship between the 3rd term and .

Step-by-step Solution
1. Set up the ratio:
2. Express the ratio in terms of :