Question

Help! Please do a,b,c and d with explanation

Answer 1

Answer:

  a.  235°

  b. 146.03 km

  c. 105 km

  d. 193 km

Step-by-step explanation:

a. The bearing of E from A is given as 55°. The bearing in the opposite direction, from E to A, is this angle with 180° added:

  bearing of A from E = 55° +180° = 235°

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b. The internal angle at E is the difference between the external angle at C and the internal angle at A:

  ∠E = 134° -55° = 79°

The law of sines tells you ...

  CE/sin(∠A) = CA/sin(∠E)

  CE = CA(sin(∠A)/sin(∠E)) = (175 km)·sin(55°)/sin(79°) ≈ 146.03 km

  CE ≈ 146 km

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c. The internal angle at C is the supplement of the external angle, so is ...

  ∠C = 180° -134° = 46°

The distance PE is opposite that angle, and CE is the hypotenuse of the right triangle CPE. The sine trig relation is helpful here:

  Sin = Opposite/Hypotenuse

  sin(46°) = PE/CE

  PE = CE·sin(46°) = 146.03 km·sin(46°) ≈ 105.05 km

  PE ≈ 105 km

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d. DE can be found from the law of cosines:

  DE² = DC² +CE² -2·DC·CE·cos(134°)

  DE² = 60² +146.03² -2(60)(146.03)cos(134°) ≈ 37099.43

  DE = √37099.43 ≈ 192.6 . . . km

  DE is about 193 km