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Find the remaining sides and angles. Round your answers to the nearest tenth. Show your work.

Find the remaining sides and angles. Round your answers to the nearest tenth. Show-example-1
User Pedro Braz
by
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1 Answer

5 votes
Answer: These are all the sides and angles:
a = 3
b = 18.76
c = 19
A = 9.1°
B = 80.9°
C = 90°

Step-by-step explanation:


As per the usual convention the side c is opposite to the angle C, side a is opposite to angle a, and side b is opposite to angle B.

That means that c is the hypotenuse of the triangle.


Then, a is one leg, and b is the other leg.


Therefore, you can use Pythagorean theorem to find the unknown leg, b:

c² = a² + b² ⇒ b² = c² - a²
⇒ b² = 19² - 3² = 352
⇒ b = √352 = 18.76

Now you can use any trigonometric ratio to find one of the unknowm angles.

I wll use sine ratio to find the angle opposite to a:


sin (A) = a / 19 = 3 / 19

⇒ A = arcsin (3/19) ≈ 9.1°.

Then, the other angle is: B = 180° - 9.1° - 90° = 80.9°

And those are all the sides and angles:
a = 3
b = 18.76
c = 19
A = 9.1°
B = 80.9°
C = 90°

User Chakshu
by
5.1k points