Answer:
Step-by-step explanation:
The figure shows a right triangle.
To calculate the measure of the angle A, you can use the inverse trigonometric function arctangent:
Identify the angle 
, the opposite side and the adjacent side:
Substitute into .
The measure of the angle A is:
Rounded to the nerarest hundreth:
8,3 and 5 would be my guess
Answer:
2.1
Step-by-step explanation:
By the Law of Cosines,
a² = 5² + 6² - 2(5)(6)cos(20°)
a = sqrt(5² + 6² - 2(5)(6)cos(20°)), which is about 2.1
Since we know the polygons are similar, the side length ratio of each side must be equal.
13/5 = x/10
Multiply both sides by 10
x = 26
That's your answer. Have a nice day! :)
