Monday

September 22, 2014

September 22, 2014

Posted by **Bobby** on Tuesday, June 29, 2010 at 3:59pm.

Given that

A=46 degree

b=4

c=8

- trig -
**bobpursley**, Tuesday, June 29, 2010 at 4:38pmIs this a triangle?

Law of Cosines:

a^2=b^2+c^2-2bcCosA

solve for a.

Then, law of sines:

sin46/a=sinB/b

solve for sinB, then B

- trig -
**Henry**, Tuesday, June 29, 2010 at 5:20pmLAW OF COSINES: CosA=(b^2+c^2-a^2)/2bc

Cos46=(16+64-a^2)/2*4*8.

Cos46=(80-a^2)/64, 80-a^2=64Cos46,

a^2=80-64Cos46=35.54, a=5.96=6.0

LAW of SINES: SinB/b=SinA/a

SinB/4=Sin46/6,Multiply both sides by 4: SinB=4*Sin46/6=0.4791, B=28.66=28.7

- trig -
**bobpursley**, Tuesday, June 29, 2010 at 5:28pmand easy way to check this is to grab your protractor and sketch it to see if it works.

**Answer this Question**

**Related Questions**

Johan - Given angle 1 = (x + 7)degree, angle 2 = *(2x -3)degree, angle ABC = (x ...

math - Find an angle between 0 degree and 360 degree that is coterminal with ...

trig - given the following values, what is angle B? A= 46 degree b= 4 c= 8

math - In triangle ABC, angle B = 3, angle A and angle C = 8 angle A. How many ...

Trig-Value of angle degree - For the angle degree 0, i don't understand how for ...

math - using a ruler and a pair of compass only construct a quadrilateral PQRS...

trig - Given angle x,where 0 <= x <= 360 (degrees) solve for to the ...

trig - When the sun's angle of elevation is 30 degree the shadow of a post is 6 ...

Geometry - Angle Construction - I need to construct a 75 degree angle. I was ...

Math - Int Trig - Form a polynomial f(x) with real coefficients having the given...