Answer
Cosine ratio, $θ \approx 58^{\circ}$
Work Step by Step
1. Find the base of the triangle
$= \frac{26-10}{2}$
$= \frac{16}{2}$
$= 8$ ft
2. Find the ratio and angle
$cos = \frac{adjacent}{hypotenuse}$
$cos(θ) = \frac{8}{15}$ (Cosine ratio)
by GDC / calculator
$θ = 57.769...^{\circ}$
$θ \approx 58^{\circ}$
