The Law of Cosines features the 3 side lengths of a triangle, plus the measure of the angle opposite one of those sides.
We want angle x, which is opposite the side of length 39.
Then: a^2 = b^2 - 2ab cos C becomes 39^2 = 36^2 + 59^2 - 2(36)(59)cos x
or 1521 = 3481 + 1296 - 2(36)(59) cos x
Subtract (3481+1296) from both sides: 1521 - 4777 = -4248cos x
-3256 = -4248cos x
-3256
Then: cosx = --------------- = 0.766
-4248
Solving for x: x = arccos -0.766 = 0.698 radian, or 40 degrees (answer)
Answer:
6.5 miles in 1 hour and they will run 75% of the full distance in 1 hour.
Step-by-step explanation:
The distance covered by two marathon runners = 26 miles
They takes 4 hours
We need to find how many miles did they run in 1 hour
In 4 hour, the distance covered is 26 miles
To find distance covered in 1 hour, divide 26 by 4 such that.

So, they will cover 6.5 miles in 1 hour.
For percentage,

So, they will run 75% of the full distance in 1 hour.