Answer:
The length of the wire is 76.19 m.
Explanation:
It is given that a guy wire is attached to the top of a radio antenna and to a point on horizontal ground that 40 m from the base of the antenna.
It means base of the right angled triangle is 40 m.
The wire makes an angle of 58deg 20min with the ground.
1 degree = 60 min
Using this conversion convert the given angle in degree.
![58^(\circ)20'=58^(\circ)(20)/(60)^(\circ)=58(1)/(3)^(\circ)=(175)/(3)^(\circ)](https://img.qammunity.org/2020/formulas/mathematics/college/j1ko1kxz9bkosohub0efbfjl0mb5r540sj.png)
In a right angled triangle
![\cos \theta=(adjacent)/(hypotenuse)](https://img.qammunity.org/2020/formulas/mathematics/college/v7sppn2srqzzpc01qj0dcyyqq2gk0km6uw.png)
![\cos ((175)/(3)^(\circ))=(40)/(hypotenuse)](https://img.qammunity.org/2020/formulas/mathematics/college/k2oq4qnoudxjiq73w826mgh5yd4oy9r48d.png)
![0.525=(40)/(hypotenuse)](https://img.qammunity.org/2020/formulas/mathematics/college/z60dsc3563rvitp861ptgif2nwuvdmbv66.png)
![hypotenuse=(40)/(0.525)](https://img.qammunity.org/2020/formulas/mathematics/college/38topj3fvm1623lob7ige5tfhu1yh0w0ou.png)
![hypotenuse=76.190](https://img.qammunity.org/2020/formulas/mathematics/college/do0t7zvuj56wfm5zi9r2987ni35m9du74h.png)
Therefore the length of the wire is 76.19 m.