SOLUTION: A flower bed in the shape of a right triangle is to be made in the corner of a yard, with sides 15 feet and 20 feet. a) The label the fertilizer I plan to use for the flower bed

Algebra ->  Triangles -> SOLUTION: A flower bed in the shape of a right triangle is to be made in the corner of a yard, with sides 15 feet and 20 feet. a) The label the fertilizer I plan to use for the flower bed      Log On


   

Question 271106: A flower bed in the shape of a right triangle is to be made in the corner of a yard, with sides 15 feet and 20 feet.
a) The label the fertilizer I plan to use for the flower bed says to use 2 cups for each 100 square feet. How much will I need? The answer I got was 6 cups.
b) I want to add 6 inches of topsoil on the flower bed, which comes in bags that hold 2 cubic feet each. How many bags will I need?
c)How many feet of fencing will be needed to completly surround the flower bed?
The answer I got was 145ft.
Please help me with the (B) question and correct (A and C) if I got those wrong. Thanks so much.
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


A: The area of a triangle is given by



where is the measure of the base and is the measure of the height (aka altitude). In a right triangle, the base and height are the same as the legs of the triangle. So in your case:



Then







B: From part A, the area is 150 ft². If you want the topsoil to be 6 inches deep, you use one-half cubic foot for every square foot of area. Or 75 cubic feet for the entire 150 ft² garden. 75 divided by 2 is 37.5, so you need 38 bags of soil unless you can get someone to sell you half a bag.

C: The perimeter is just the sum of the measures of the sides. 15 is to 20 as 3 is to 4, so this is actually a 3-4-5 right triangle, and the hypotenuse is 25. (if you want to check this, use Pythagoras: ) The perimeter is then 15 + 20 + 25 = 65 feet.


John