For this case what we must do is use the law of cosines.
We then have the following equation:
[tex]c ^ 2 = a ^ 2 + b ^ 2 - 2 * a * b * cos (x)
[/tex]
Where,
a, b: sides of the triangle
x: angle between sides a and b.
Substituting values we have:
[tex]c^2 = 90^2 + 75^2 - 2*90*75*cos(85)
[/tex]
Clearing the value of c we have:
[tex]c = \sqrt{ 90^2 + 75^2 - 2*90*75*cos(85)} [/tex]
Answer:
An expression that is equivalent to how many feet the oak trees are from each other is:
[tex]c = \sqrt{ 90^2 + 75^2 - 2*90*75*cos(85)} [/tex]