Okay so we did 2 questions in class on Friday:
1. How many triangles, ABC, are possible with a=4, b=7 and angle A=30 degrees?
For most people, drawing the picture first helps out a lot, so here is one possibility:
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Now you can figure out sinB because you know 2 sides and 1 angle. Heres how:
sin30/4 = sinB/7
sinB = 7sin30/4
sinB = 0.875
To find the angle, on you're calculator you do inverse sine of 0.875.
angle B = 61 degrees
You know you can make a triangle with that because you know 2 angles and when you add them they do not add up to 180 which makes it possible to have another angle.
The calculator only gives you the angle in quadrant I but there can also be an angle in quadrant II which you can figure out by taking the angle you got and subracting it from 180.
In this case, angle B can also = 119 degrees. Therefore, you can make 2 triangles.
THE NEXT SCRIBE IS.. NATNAEL!! (sorry for taking so long)
Who is the Next Scribe!?!
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