Answer:
B = 612.2 ft
Step-by-step explanation:
Solution:-
- The elevation of person, H = 235 ft
- The angle of depression, θ = 21°
- We will sketch a right angle triangle with Height (H), and Base (B) : the boat's distance to the edge of the cliff and the angle (θ) between B and the direct line of sight distance.
- We will use trigonometric ratios to determine the distance between boat and the edge of the cliff, using tangent function.
tan ( θ ) = H / B
B = H / tan ( θ )
B = 235 / tan ( 21 )
B = 612.2 ft
Step-by-step explanation:
1. No: angles add to more than 180 deg.
2. Yes: each side's length is between the sum and difference of the lengths of the other two sides.
3. No: not every side's length is between the sum and difference of the lengths of the other two sides.
4. Yes: for example, place the 50 deg angle between the two given sides. Another side will then make the triangle.
5. Yes: for example, use 3 cm as the short leg in a 30-60-90 right triangle.
Equation is y=kx. We have four chance to figure out k; hopefully they all give the same result
x=9, y=63, y=kx becomes 63=k(9) so k=63/9=7
x=4, y=28, 28=k(4), k=7
The constant of proportionality is 7; we check 2×7=14, 11×7=77
Answer: k=7, y=7x
12/30 = 18/45....cross multiply
(30)(18) = (12)(45)
540 = 540...proportional
another way to tell is to see if they are equivalent...because proportions are nothing but equivalent fractions.
12/30 = 2/5
18/45 = 2/5
so yes, they are proportional
