Law of Sines
Law of Cosines
Real Life Problems
Area of Triangles
Don't Pick This One
100
In triangle ABC, B=64 degrees, C=38 degrees, and b=9 ft. Find the lengths of sides of a and c.
a=9.79 ft c=6.16 ft
100
Find the length of the specified side. Side r in triangle RPM if p= 4 cm, m= 5 cm, and R=51 degrees.
r= 3.98 cm
100
A surveying crew has the job of measuring a mountain. From a point on the ground they measure an angle of elevation of 21.6 degrees to the top. They move 507 m closer to the mountain and find that the angle of elevation is now 35.8 degrees. How high is the mountain? (You may have to calculate some other things along the way.)
The mountain is 445.1 m high.
100
Find the area of triangle ABC if a= 13 in, b= 15 in, and C= 71 degrees.
Area= 92.188 in squared.
100
University of Louisville and the University of Kentucky
What are the colleges the seniors will be attending next year?
200
For triangle ABC, A=52 degrees, B=31 degrees, and a=8 cm. Find the lengths of sides b and c.
b=5.23 cm c=10.08 cm
200
Find angle O in triangle NOP if n=1475 yd, o= 2053 yd, and r= 1953 yd.
O= 90 degrees
200
Nadia is a pilot of an airliner who needs to detour around a group of thunderstorms. She turns her plane at an angle of 21 degrees to her original path, flies for a while, then turns back and rejoins her original path at an angle of 35 degrees, 70 km from where she left it. a. how much further did she have to fly because of the storms? b. What is the area of the region enclosed by the triangle?
a= 8.7 km b= 607.5 km squared
200
Find the area of triangle JDH if j= 5 cm, d=7 cm, and h=11 cm.
Area= 12.969 cm squared
200
7 days
What is the number of days 'til the senior's graduation
300
In triangle ABC, a= 8, b= 6, c= 7, Find the missing angles.
A= 75.5 degrees B= 46.6 degrees C= 57.9 degrees
300
Angle Y in triangle XYZ if x= 7 yds, y=5 yds, and p=13 yds.
This is not a possible triangle.
300
Elizabeth is aboard a plane destined for Hawaii. The pilot announces that the plane's altitude is 10 km. Out of boredom she decides to calculate how far away the horizon is. IN order to do this she must calculate arc length. The radius of the Earth is about 6400 km. How far away is the horizon along Earth's curved surface?
The horizon is 357.538 km away.
300
Find the area of triangle RST if r= 4.8 cm, t= 3.7 cm, and S= 43 degrees.
Area= 6.06 cm squared
300
Bellarmine, Knights Hall
What is the place the seniors graduate. :)
400
Hannah works for a construction company that is planning to build a bridge from the mainland to an island. There are two options to start the bridge from, point X and point Y, which are 1000 m apart. From point X to the island she measures a 42 degree angle, and from point Y she measures a 58 degree angle. In order to decide she must know the precise lengths of the two possible bridges and choose the shorter of the two to save costs. a.What are the precise lengths of the two bridges? b. If constructing the bridge costs $370 per meter, how much could be saved by building the shorter one?
a. x= 679.453m y= 861. 131m b. $67, 220.70 saved
400
In the triangle ABC, if A = 62°, b= 26 ft, and c= 19 ft, find the length of side a.
a= 23.94 ft
400
A surveyor measures the three sides of a triangular field and gets the following lengths: 114 m, 165 m, 257 m. a. What is the measure of the largest angle of the triangle? b. What is the area of the field?
a= 133.358 degrees b= the area is 6838.214 m squared
400
Use Heron's formula to calculate the area of triangle ABC if a= 6 cm, b= 9 cm, and c=11 cm.
Area= 26.981 cm squared.
400
Assumption
What is the school Mrs. Cook worked at before coming to Mercy?
500
Two people are standing at different distances from the base of a building and looking at the top. The person A looks at the top of the building at an angle of elevation of 45 degrees. The person B is 100 ft closer to the base and looks up at an angle of elevation of 55 degrees. What is the height of the building?
The height of the building is about 333.6 ft tall.
500
Alexis flies a helicopter to drop supplies to recent flood victims. She flies from the supply depot, S, to the drop off point, P, which is a distance of 15 miles. Then she flies to the helicopter base, B, which is 21 miles away from point P. It is 33 miles between the supply depot and the helicopter base. What is the angle of P, the angle between the two paths at drop point?
P= 132.2 degrees
500
You can use the Law of Sines to find an unknown angle measure, but this technique is risky. Suppose triangle ABC has sides of 4 cm, 7 cm and 10 cm. a. Use law of cosines to find the measure of angle A. b. Use the answer to part a (don't round) and the law of sines to find the measure of angle C.
a. A= 33.1229 degrees b. C= 51.318 degrees
500
Use Heron's formula to solve for triangle DEF if d=3.7 in, e= 2.4 in, and f= 4.1 in.
Area= 4.391 in squared
500
All our wonderful classmates :)
What is the thing we are going to miss most about our PreCal class?
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