In the given diagram: measure angle DAB + measure angle BAC = 90 degrees we are given that measure angle DAB = 10 degrees Therefore: measure angle BAC = 90 - 10 = 80 degrees
Now, triangle ABC is a right-angled triangle which means that we can use the trigonometric functions. The function that we will use is: cos theta = (adjacent) / (hypotenuse) where theta = 80 degrees adjacent = 500 hypotenuse is "x" that we want to calculate.
Substitute to get x as follows: cos 80 = 500 / x x = 500 / cos 80 = 500 / 0.1736 = 2879.4 m