211k views
3 votes
The law of cosines is used to find the measure of Q.

242 = 202 + 342 – 2(20)(34)cos(Q)

576 = 400 + 1156 – (1360)cos(Q)

576 = 1556 – (1360)cos(Q)

–980 = –(1360)cos(Q)

To the nearest whole degree, the measure of angle Q _____ is
degrees

User Autorun
by
8.2k points

2 Answers

4 votes

the right answer is 44.

User Kamagatos
by
8.0k points
4 votes

Answer:

44 degrees.

Explanation:

We are asked to find the measure of angle Q using law of cosines.

Law of cosines:


c^2=a^2+b^2-2ab* cos(C)

Upon substituting our given values in above formula we will get,


24^2=20^2+34^2-2* 20* 34* cos(Q)


576=400+1156-1360* cos(Q)


576=1556-1360* cos(Q)


576-1556=1556-1556-1360* cos(Q)


-980=-1360* cos(Q

Upon dividing both sides of our equation by -1360 we will get,


(-980)/(-1360)=(-1360* cos(Q)/(-1360)


0.7205882352941176=cos(Q)

Now we will use arccos to solve for the measure of angle Q.


cos^(-1)(0.7205882352941176)=Q


43.896932391182=Q


Q\approx 44

Therefore, the measure of angle Q is 44 degrees.

User Jimmy Lee
by
8.5k points