anonymous050
anonymous050 anonymous050
  • 03-08-2019
  • Mathematics
contestada

In △ABC,a=14, b=17, and c=22. Find m∠A.

Respuesta :

gmany
gmany gmany
  • 03-08-2019

Answer:

[tex]\large\boxed{m\angle A\approx39^o}[/tex]

Step-by-step explanation:

Use the cosine law:

[tex]a^2=b^2+c^2-2bc\cos A[/tex]

We have:

[tex]a=14,\ b=17,\ c=22[/tex]

Substitute:

[tex]14^2=17^2+22^2-2(17)(22)\cos A\\\\196=289+484-748\cos A\\\\196=773-748\cos A\qquad\text{subtract 773 from both sides}\\\\-577=-748\cos A\qquad\text{divide both sides by (-748)}\\\\\cos A=\dfrac{577}{748}\\\\\cos A\approx0.7714\to m\angle A\approx39^o[/tex]

Answer Link

Otras preguntas

In which of the following present-day areas was the Folsom culture found?
In a restaurant, Chad tracked the number of children and adults that came in over an hour. During that time, 16 children and 40 adults came in the restaurant. W
If water and oil are combined in a container, the resulting liquid is a(n) A. suspension. B. emulsion. C. mixture. D. solution.
Clusters of concentrated development on the perimeter highways of an urban area are called _____.
what is 4.45 repeating as a fraction. these are the choices: A.4 227/500 B. 4 9/20 C. 4 5/11 D. 4 9/2
Süleyman was an Ottoman emperor who created a code of laws for his empire. A. True B. False
What is the sign of the product of three integers with the same sign
what led to the creation of complex societies
What is the value of a2 + 3b ÷ c - 2d when a = 3, b = 8, c = 2, and d = 5 a. 8 b. 12 c. 10 d. 11
If c = 18, what is 2 x (74 - c)?