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Someone please help! I have spent lots of time on this and I’m still confused

Someone please help! I have spent lots of time on this and I’m still confused-example-1
User Caffiend
by
5.9k points

1 Answer

4 votes

Answer:

its the 3rd choice.

Explanation:

Firstly, we find angle BDC (180-90-30=60)

Now that we found it we can use the sine rule to find DB (which i put as an x), which is sin60/14=sin30/x, by cross multiplication, we find that its equal to a decimal number, i will use its root version to this easier, its equal to 14sqrt3/3 inches.

And now we use the pythagorean theorem to find DC, we find that it is equal to 28sqrt3/3

Now, we find angle BAC (180-90-(30+15)=45)

Again, we use the sine rule to find AB (whom i will refer to as x and from whom we will subtract DB to find the length of AD), so we cross multiply in sin45/14=sin(30+15)/x, it is equal to 14.

So since AB-DC=AD

14-(14sqrt3/3)= 5.917096231 (and we ound that to a 5.9)

User Anudeep
by
7.0k points
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