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34 votes
Help with question b please​

Help with question b please​-example-1
User Murat Aslan
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1 Answer

10 votes
10 votes

9514 1404 393

Answer:

(a) 5.82 cm (correctly shown)

(b) 10.53 cm

Explanation:

a) The length BC can be found from the law of sines:

BD/sin(C) = BC/sin(D)

BC = BC·sin(C)/sin(D) = (6 cm)sin(48°)/sin(50°) ≈ 5.82 cm

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b) The angle ABD is the sum of the angles shown:

angle ABD = 50° +48° = 98°

We know the lengths BA and BD and the included angle ABD, so we can use the law of cosines to find AD.

AD² = BA² +BD² -2·BA·BD·cos(98°)

AD² ≈ 8² +5.82² -2(8)(5.82)(-0.139173) ≈ 110.8411

AD ≈ √110.8411 ≈ 10.53 . . . . cm

User LFLFM
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