sine angles?

Question

1. in a right triangle ABC, the hypotenuse AB=127 and the acute angle A = 20 degrees. What is the lengh of CB?

2. in a right triangle ABC, C being the right angle, AB = 2.4 and angle B = 80 degrees. What is the length of AC?

Answer 1

1. sin(20)*127

2. sin(80)*2.4

Answer 2

Dont listen to blah...,

the sine of an angle in a right triangle always gives you the length of the side opposite the angle for a triangle with a hypotenuse of length 1, after you just multiply by length of the hypotenuse to scale the triangle to size you want. so in the triangle

A



C B

BC= AB*sine(A)

just have to pull out the calculator

Answer 3

Well, it would be sin 20 = CB/127. So, 127 sin 20 is the measure of CB.

It would be sin 80=AC/2.4. So, 2.4 sin 80 is the measure of AC.

Answer 4

draw a suitable triangle. because of the fact that sine = opp/hyp, you are able to label the different area as 3, and the hypotenuse as 5. you are able to desire to understand adj/hyp to understand the cosine, so which you will desire to remedy for the third area using the pythagorean theorem. 5^2 = 3^2 + x^2 x^2 = 5^2 - 3^2 x^2 = sixteen x = 4 (detrimental discarded because of the fact that distance is often valuable). So label the in simple terms suitable area 4, and then ofcourse the cosine is 4/5.

Answer 5

a/sinA = b/sinB = c/sinC

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1) 127/sin90 = BC/sin20

127 = BC/sin20

127 * sin20 = BC

BC = 43.437

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2) 2.4/sin90 = AC/sin80

2.4 = AC/sin80

2.4 * sin80 = AC

AC = 2.364