The Sine and Cosine RulesRight-angled triangle Trigonometry
Please note your working out with your answer, thank you.
Q11) A lifeguard on top of an observation tower 12.5m high notices a surfer in trouble at an angle of depression of 8 degrees. How far, correct to one decimal place, is the surfer from the tower?
Q13) A boat is 420m from the base of the cliff. The angle of depression of the boat from the top of the cliff is 28 degrees. Find the height of the cliff to the nearest metre.
Answers
I am not doing that with sin, cos and pythagorean theorem.
DEFINITION: we call TAN x=sin x / cos x
This means that in a right triangle the tangent of an angle is the ration of opposed side by adjacent side.
11: tan 8°=12.5/d
==>d=12.5/tan 8°=12.5/0.14054...=88.942121...m≈88.9 (m)
12:
tan 28°=h/420
==>h=420*tan 28°=420*0.5317...=223.3179...≈223.3 (m)
Related Questions
HELP MEEE!7th grade mathhhh
Which expression is equivalent to 2 + 3?A) 3 - 2 B) 3 + 2 C) 3(2) EliminateD) 6
Four coins are tossed several times. Which of the following represents the outcome on a coin that may not be fair? 1st coin is tossed 50 times and gives 24 heads and 26 tails. 2nd coin is tossed 250 times so that P(heads) = 0.25. 3rd coin is tossed 16 times and gives P(tails) = 9/16 4th coin is tossed 25,000 times and gives 12,505 heads.
If (x^2 – 4) ÷ (x + 2) = x – 2, which polynomial should fill in the blank below?(x + 2) ´ ______ = x^2 – 4 A. x^2 – 4 B. x – 2 C. x + 2 D. x^2 – 2
Answers
Answer:
x=4
Step-by-step explanation:
, and do not round your answer. Be sure to include the correct unit in your answer.
Answers
Area of circle= Pi x radius2 (this means radius squared)
Area of triangle= 1/2 x base x height
1/2 (because it is a semi circle) x 3.14 (in replacement of pi as directed by question) x 9squared= 127.17
127.17 - (1/2 x 18 x 9) = 46.17cmsquared
Final answer:
The area of the shaded region can be found by subtracting the area of the triangle from the area of the semicircle.
Explanation:
To find the area of the shaded region, we need to calculate the area of the semicircle and subtract the area of the triangle from it. First, let's find the area of the semicircle. The formula to find the area of a semicircle is A = (π * ) / 2, where π is approximately 3.14 and r is the radius. Plugging in the values, we have A = (3.14 *
) / 2 = 127.26 square cm.
Next, let's find the area of the triangle. The formula to find the area of a triangle is A = (base * height) / 2. In this case, the base of the triangle is the diameter of the semicircle, which is 2 * 9 = 18 cm. The height of the triangle is the radius of the semicircle, which is 9 cm. Plugging in the values, we have A = (18 * 9) / 2 = 81 square cm.
Finally, to find the area of the shaded region, we subtract the area of the triangle from the area of the semicircle: 127.26 - 81 = 46.26 square cm. So, the area of the shaded region is 46.26 square cm.
Learn more about shaded region
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b. Write an equation to model the problem. Explain your answer.
c. Solve the equation. Show your work.
d. Find the number of minutes that Allegra went over the time that the plan allows. Explain your answer.
Please help me with this problem, I don’t understand it. Thanks in advance! :D
Answers
a. The unknown is how many minutes she used beyond the plan. So, we'll use "m" for the variable, to represent minutes.
b. 73.40 = 65 + 0.10m
The 73.40 is the total, which is why it's by itself. 65 represents the price per month for the plan, and 0.10m is the price per extra minute multiplied by the unknown amount of minutes used.
c. 73.40 = 65 + 0.10m
8.40 = 0.10m
84 = m
d. The number of minutes that Allegra went over the time that the plan allows is found by solving the equation we just wrote and solved. $0.10 is paid for every minute past the plan's allowance, meaning that "m" in the equation, when solved, shows us exactly how many minutes over Allegra went.
B.25
C.50
D.100
Answers
Answers
The value of the expression 45 - 0.023 is 44.97
What are expressions?
An expression is a sentence with at least two numbers or variables having mathematical operation. Math operations can be multiplication, addition, subtraction, division.
For example, 2x+ 4
Given that,
The expression
⇒ 45 - 0.023
Now subtracting number 0.023 from the number 45
the number 45 is a integer
the number 0.023 is a decimal number
⇒ 44.97
Hence, the value of expression is 44.97
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- 00.023
_________
44.977
Answers
So first add
5m + 4m = 9m
Now lets set up our equation again
9m = 72 .... divide both sides by 9 to get m alone
÷9 = ÷9
************ now m is alone on the left side and we solve on the right side.
m = 8
So your answer is
m = 8
Hello my friend
9m=72
Divide both sides by 9 so you can find the value for m
9m/9=72/9
m=8
I hope that's help:)