Final answer:
The length of the longer side of the parallelogram is approximately 44.45 inches.
Step-by-step explanation:
The diagonals of a parallelogram divide it into four congruent triangles. We can use the Law of Cosines to find the length of the longer side. Let's call the length of the longer side 'x'. Using the Law of Cosines, we have:
x^2 = 40^2 + 42^2 - 2(40)(42)cos(40)
Simplifying the equation, we find that x ≈ 44.45 inches.