118k views
1 vote
Can someone please explain to me how to get this answer?

Can someone please explain to me how to get this answer?-example-1
User Mstrom
by
8.8k points

2 Answers

0 votes

Answer:

33,2 ≈ c

45 ≈ b

120° = A

Step-by-step explanation:

We will be using the Law of Sines:

Solving for Angle Measures


( \sin∠C)/(c) = ( \sin∠B )/(b) = ( \sin∠A)/(a)

** In the end, use the sin⁻¹ function or else you will throw off your answer.

Solving for Sides


(c)/( \sin∠C) = (b)/( \sin∠B) = (a)/( \sin∠A)

Given instructions:

  • 68 = a
  • 25° = C
  • 35° = B

Well, the first thing we can do is to find the m∠A, and we have to use the Triangular Interior Angles Theorem:

25° + 35° + m∠A = 180°

|________|

60° + m∠A = 180°

-60° - 60°

__________________

m∠A = 120°

Now that we have the third angle measure, we can use it in the formula to find the other sides of the triangle, like side c:


(c)/( \sin 25°) = (68)/( \sin 120°) \\ \\ (68 \sin 25°)/( \sin 120°) ≈ 33,18383234 ≈ 33,2 \\ \\ 33,2 ≈ c

Now, we have to find side b:


(b)/( \sin 35°) = (68)/( \sin 120°) \\ \\ (68 \sin 35° )/( \sin 120° ) ≈ 45,03701335 ≈ 45 \\ \\ 45 ≈ b

Now everything has been defined!

I am joyous to assist you anytime.

User Faulty
by
8.6k points
4 votes
Answers:
A = 120
b = 45.0
c = 33.2

Side Note: only one triangle is possible
See attached for a visual. I used GeoGebra to draw the triangle.

-------------------------------------------------------------
-------------------------------------------------------------

Step-by-step explanation:

We are given the following information
B = 35
C = 25
a = 68

We need to find the following
A, b, c

where the lower case letters represent the side lengths; the upper case letters are the angles. The angles are opposite their corresponding sides. For instance, side lowercase b is opposite angle uppercase B. The other letters are positioned the same way.

-----------------------

First use the idea that for any triangle, the three angles (A,B,C) must add to 180 degrees
A+B+C = 180
Replace B and C with 35 and 25. Solve for angle A
A+35+25 = 180
A+60 = 180
A+60-60 = 180-60
A = 120

Now that we know the three angles A = 120, B = 35, C = 25, we can find the missing sides 'b' and 'c'

-----------------------

We will use the law of sines to find side b
sin(A)/a = sin(B)/b
sin(120)/68 = sin(35)/b
b*sin(120) = 68*sin(35) <<--- cross multiply
b = 68*sin(35)/sin(120)
b = 45.037013350222 <<--- use a calculator; this value is approximate
b = 45.0 <<--- round to the nearest tenth

-----------------------

Do the same for side c
sin(A)/a = sin(C)/c
sin(120)/68 = sin(25)/c
c*sin(120) = 68*sin(25) <<--- cross multiply
c = 68*sin(25)/sin(120)
c = 33.1838323365404 <<--- use a calculator; this value is approximate
c = 33.2 <<--- round to the nearest tenth
Can someone please explain to me how to get this answer?-example-1
User MacMark
by
7.2k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories