Question

Emma is on a 50 m high bridge and sees two boats anchored below. From her position, boat A has a bearing of 230° and boat B has a bearing of 120°. Emma estimates the angles of depression to be about 38° for boat A and 35° for boat B. How far apart are the boats to the nearest meter?

243

likes
1214 views

Answer to a math question Emma is on a 50 m high bridge and sees two boats anchored below. From her position, boat A has a bearing of 230° and boat B has a bearing of 120°. Emma estimates the angles of depression to be about 38° for boat A and 35° for boat B. How far apart are the boats to the nearest meter?

Expert avatar
Jayne
4.4
106 Answers
In this diagram, point A represents Emma's position on the bridge, point B represents boat A, and point C represents boat B. We know that the height of the bridge is 50 meters, and the angles of depression to boats A and B are 38° and 35°, respectively. We also know that the bearings of boats A and B are 230° and 120°, respectively. We can use the tangent function to find the distances from Emma to boats A and B. For boat A, we have: tan(38°) = 50 / d_A Solving for d_A, we get: d_A = 50 / tan(38°) = 64.1 meters Similarly, for boat B, we have: tan(35°) = 50 / d_B Solving for d_B, we get: d_B = 50 / tan(35°) = 71.4 meters Now that we know the distances from Emma to boats A and B, we can use the Law of Cosines to find the distance between the two boats. The Law of Cosines states that: c^2 = a^2 + b^2 - 2ab * cos(C) where c is the distance between the two points, a and b are the distances to the two points from a third point, and C is the angle between the lines connecting the third point to the two other points. In this case, we have: c = d_A + d_B a = 50 meters b = 50 meters C = 110° Substituting these values into the Law of Cosines, we get: (d_A + d_B)^2 = 50^2 + 50^2 - 2 * 50 * 50 * cos(110°) Solving for c, we get: c = sqrt((d_A + d_B)^2 - 50^2 - 50^2 + 2 * 50 * 50 * cos(110°)) Plugging in the values for d_A and d_B, we get: c = sqrt((64.1 + 71.4)^2 - 50^2 - 50^2 + 2 * 50 * 50 * cos(110°)) Evaluating this expression, we get: c = 111.4 meters Therefore, the distance between the two boats is approximately 111 meters to the nearest meter.

Frequently asked questions (FAQs)
What is the dot product of vectors u = [3, -1, 2] and v = [4, 2, -3]?
+
Math question: Graph the inequality 3x - 2y ≤ 6.
+
What is the measure of angle C in a triangle with sides of lengths 8, 11, and 15, using the cosine law?
+
New questions in Mathematics
Let 𝑢 = 𝑓(𝑥, 𝑦) = (𝑒^𝑥)𝑠𝑒𝑛(3𝑦). Check if 9((𝜕^2) u / 𝜕(𝑥^2)) +((𝜕^2) 𝑢 / 𝜕(𝑦^2)) = 0
what is 9% of 307
In a random sample of 600 families in the Metropolitan Region that have cable television service, it is found that 460 are subscribed to the Soccer Channel (CDF). How large a sample is required to be if we want to be 95% confident that the estimate of “p” is within 0.03?
2x+4x=
sin 30
6-35 A recent study by an environmental watchdog determined that the amount of contaminants in Minnesota lakes (in parts per million) it has a normal distribution with a mean of 64 ppm and variance of 17.6. Assume that 35 lakes are randomly selected and sampled. Find the probability that the sample average of the amount of contaminants is a) Greater than 72 ppm. b) Between 64 and 72 ppm. c) Exactly 64 ppm. d) Greater than 94 ppm.
Exercise 1 An ejidal association wishes to determine the distribution for the three different crops that it can plant for the next season on its available 900 hectares. Information on the total available and how many resources are required for each hectare of cultivation is shown in the following tables: Total available resource Water 15,000 m3 Fertilizer 5,000 kg Labor 125 day laborers Requirements per cultivated hectare Corn Soybeans Wheat Water 15 25 20 Fertilizer 5 8 7 Labor** 1/8 1/5 1/4 *The data in fraction means that with one day laborer it will be possible to care for 8, 5 and 4 hectares respectively. * Sales of crops 1 and 3, according to information from the Department of Agriculture, are guaranteed and exceed the capacity of the cooperative. However, soybeans must be limited to a maximum of 150 hectares. On the other hand, the profits for each hectare of crop obtained are estimated at: $7,500 for corn, $8,500 for soybeans and $8,000 for wheat. The objectives are to determine: • How many hectares of each crop must be allocated so that the profit is maximum. R= • The estimated profits for the ejidal cooperative in the next growing season. R=
4+168×10³×d1+36×10³×d2=-12 -10+36×10³×d1+72×10³×d2=0
Two minus log 3X equals log (X over 12)
A teacher has 25 red and yellow counters altogether. She has 4 times as many red counters than yellow counters. How many yellow counters does the teacher have?
Solve equations by equalization method X-8=-2y 2x+y=7
Show work on 4108 divided by 4
2.380× (1+0.05) / 0.95−0.05
viii. An ac circuit with a 80 μF capacitor in series with a coil of resistance 16Ω and inductance 160mH is connected to a 100V, 100 Hz supply is shown below. Calculate 7. the inductive reactance 8. the capacitive reactance 9. the circuit impedance and V-I phase angle θ 10. the circuit current I 11. the phasor voltages VR, VL, VC and VS 12. the resonance circuit frequency Also construct a fully labeled and appropriately ‘scaled’ voltage phasor diagram.
Which statement best describes the key changes in perspectives on inclusion? An inclusive program must consider the unique experiences of every child and family as well as the child's strengths and needs. There is a shift in thinking about individual programs as "inclusive programs" to thinking about inclusion as something that reflects the cultural influence of the family. There is a greater emphasis on barriers to full participation and the acknowledgement that all children are unique and must be fully and meaningfully engaged in a program. In an inclusive program all participants are accepted by their peers and other members of the community.
Calculate the area of the parallelogram with adjacent vertices (1,4, −2), (−3,1,6) 𝑦 (1, −2,3)
If the mean of the following numbers is 17, find the c value. Produce an algebraic solution. Guess and check is unacceptable. 12, 18, 21, c, 13
The mean of 4 numbers is 5 and the mean of 3 different numbers is 12. What is the mean of the 7 numbers together? Produce an algebraic solution. Guess and check is acceptable.
A group of 17 people spent 9 days on vacation and spent R$776.34 on barbecue meat and the bill needs to be divided as follows: 6 people stayed for 9 days, 7 people stayed for 4 days, and 2 people stayed for 5 days and 2 people stayed 3 days, how much does each group have to pay for the days they stayed?
12[4 + (8 + 7) + 5]