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26 votes
26 votes
Part B The seesaw moves and the angle created by the left of the seating board and the central support is now 70°. Seating Board R S 70 Central Support Find the distance from point Q to the ground when the angle created by the left side of the seating board and the central support is 70 ° (the length of the dashed line). Show your work or explain your answer. Round your answer to the nearest tenth of a foot. Enter your answer, and your work or explanation in the space provided

User Rendicahya
by
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1 Answer

16 votes
16 votes

In order to determine the distance from the point Q until the ground, it is necesary to know the length of the support. It is obtained from the part A of the question, as follow:

d = 5 ft · sin 30° = 2.5 ft

Next, consider, that the line that connects point R and the ground trought Q is the hypotenuse of a triangle. In this case, the length of the support is the adjacent side to the angle 70°. With this information and by using the cosine of the angle 70°, you can obtain the distance from R to the ground trough Q, as follow:

RG: distance from R to the ground (hypotenuse)

cos 70° = length of the support / RG solve for GR

cos 70° = 2.5 ft/ RG

RG = 2.5 ft/ cos 70°

RG = 7.3 ft

Next, to the previous value, subtract the lenght of segment RQ = 5 ft:

Distance from point Q to the ground trough dotted line = 7.3 ft - 5 ft = 2.3 ft

Hence, th answer is 2.3 ft

User Bulki
by
3.0k points
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