Answer:
the base of the tree from a stake anchoring the wire is 18.7 ft long
Step-by-step explanation:
A guy wire for a tree is 20 ft. long, making a 21 degree angle with the ground.
It forms a right angle triangle. the hypotenuse of the triangle is 20 ft
The adjacent side of the given angle 21 degree is the base of the tree from a stake
Let x be the base length
[tex]cos(theta)=\frac{adjacent}{hypotenuse}[/tex]
[tex]cos(21)=\frac{x}{20}[/tex]
[tex]20cos(21)=x[/tex]
[tex]x=18.7[/tex]
the base of the tree from a stake anchoring the wire is 18.7 ft long