4 1/5 + b = 9 3/5
4 1/5 - 4 1/5 + b = 9 3/5 - 4 1/5
(taking the same amount from each side to keep it balanced)
0 + b = 5 2/5
(subtracting 4 1/5 from each side)
b = 5 2/5
4 2/5 x 10 = 4x 10 + 2/5 * 10
40 + 4 = 44
26 x 2 1/2 = 26 x 2 + 26 * 1/2
52 + 13 = 65
For this case what we must do is use the law of cosines.
We then have the following equation:

Where,
a, b: sides of the triangle
x: angle between sides a and b.
Substituting values we have:

Clearing the value of c we have:
Answer:
An expression that is equivalent to how many feet the oak trees are from each other is:
Answer is 5 because the other sides are 9 each