To find side a of triangle ABC, we can use the law of cosines, which states that:
a² = b² + c² - 2bc cos(A)
Substituting the given values, we get:
a² = 3.5² + 7.2² - 2(3.5)(7.2)cos(114°)
Simplifying, we get:
a² = 12.25 + 51.84 - 50.4(-0.3917)
a² = 12.25 + 51.84 + 19.77
a² = 83.86
Taking the square root of both sides, we get:
a ≈ 9.2
Therefore, side a of triangle ABC is approximately 9.2 meters.