SOLUTION: 1. Identify the indicated sum. Image: http://my.thinkwell.com/questionbank/94001-95000/94420/img/245513.gif Options: −660 −330 330 660 2. Identif

Algebra ->  Equations -> SOLUTION: 1. Identify the indicated sum. Image: http://my.thinkwell.com/questionbank/94001-95000/94420/img/245513.gif Options: −660 −330 330 660 2. Identif      Log On


   



Question 984965: 1. Identify the indicated sum.
Image:
http://my.thinkwell.com/questionbank/94001-95000/94420/img/245513.gif
Options:
−660
−330
330
660
2. Identify the graph that represents an angle in standard position with the measure -140.
Options:
http://my.thinkwell.com/questionbank/94001-95000/94450/img/236989.jpg
http://my.thinkwell.com/questionbank/94001-95000/94450/img/236990.jpg

http://my.thinkwell.com/questionbank/94001-95000/94450/img/236991.jpg
http://my.thinkwell.com/questionbank/94001-95000/94450/img/236992.jpg
3. Use the given measurements to solve ΔABC. Round to the nearest tenth.
a = 15, b = 11, c = 7
Options:
m∠A ≈ 25.8°; m∠B ≈ 43.2°; m∠C ≈ 110.9°
m∠A ≈ 43.2°; m∠B ≈ 110.9°; m∠C ≈ 25.8°
m∠A ≈ 110.9°; m∠B ≈ 25.8°; m∠C ≈ 43.2°
m∠A ≈ 110.9°; m∠B ≈ 43.2°; m∠C ≈ 25.8°








Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
.
1.Indicated sum:
c=-3 (coefficient of k), n=15, x=constant=2
(1/2)cn(n+1)+2(x)
(1/2)(-3)(15)(16)+2(15)
-360+30=-330 ANSWER: -330
.
2. Standard position starts on x-axis pointing positive from origin turning counterclockwise.
The negative angle would turn clockwise so the answer is the third, 236991.jpg
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3. Law of Cosines:
.
cosA=%28b%5E2%2Bc%5E2-a%5E2%29%2F2bc
.
A=arccos%28%28b%5E2%2Bc%5E2-a%5E2%29%2F2bc%29
.
cosB=%28c%5E2%2Ba%5E2-b%5E2%29%2F2ca
.
B=arccos%28%28c%5E2%2Ba%5E2-b%5E2%29%2F2ca%29
.
A+B+C=180 degrees
C=180-A-B
.
Just fill in values: a=15; b=11; c=7
.
A=arccos%28%2811%5E2%2B7%5E2-15%5E2%29%2F2%2811%29%287%29%29
A=arccos%28-55%2F154%29
A=arccos%28-0.3571%29
A=110.9degrees
.
Try the rest on your own. Equations given above.
.
NOTE: Please limit questions to one per post in the future.