SOLUTION: In the design of a new building., a doorway is 2.65 ft above the ground. A ramp for the disabled, at an angle of 6.0 degrees with the ground, is to be built to the doorway. How lon

Algebra ->  Trigonometry-basics -> SOLUTION: In the design of a new building., a doorway is 2.65 ft above the ground. A ramp for the disabled, at an angle of 6.0 degrees with the ground, is to be built to the doorway. How lon      Log On


   



Question 624353: In the design of a new building., a doorway is 2.65 ft above the ground. A ramp for the disabled, at an angle of 6.0 degrees with the ground, is to be built to the doorway. How long will the ramp be?
Thank you in advance

Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
Draw a right triangle with horizontal and vertical sides. Label the vertical side as 2.65 ft. Label the angle between the horizontal side and the hypotenuse as 6 degrees. We are looking for the length of the ramp, which is the hypotenuse, so label it "x".

To find the length of the ramp we will need to use a Trig function the involves the angle and side we know and the side we want to know. The vertical side is the side opposite to the 6 degree angle and the ramp is the hypotenuse. Which functions have ratios involving opposite and hypotenuse? Answer: sin and csc. Since 6 degrees is not a special angle we will need to use our calculator. And since our calculator probably has a button for sin but not one for csc, we will use sin. Since sin is opposite over hypotenuse the equation we have is:
sin%286%29+=+2.65%2Fx
Now we solve this for x. We can get rid of the fraction by multiplying both sides by x:
x%2Asin%286%29+=+2.65
And then we divide by sin(6):
x+=+2.65%2Fsin%286%29
This is an exact expression for the answer. For a decimal approximation we reach for our calculators. First we find sin(6):
x+=+2.65%2Fsin%286%29
x+=+2.65%2F0.10452846
x+=+25.35194721
So the ramp will be approximately 25.35 feet long.