If I have the vertical height and the radius (of the base) of a cone, how to I get its slanted height (ie the length of the side going from top to bottom)? It's wrecking my head! Cheers :)
PS. e.g. r=2.5cm h=6cm, find L
2007-01-16 07:45:06 · 4 answers · asked by Joe Dull 2 in Science & Mathematics ➔ Mathematics
You can use Pythagora's theorem to find its slant height
L^2 = r^2 + h^2
L = (2.5^2 + 6^2)^ 1/2
L= (6.25 + 36) ^ 1/2
Therefore, L = 6.5
2007-01-16 07:52:53 · answer #1 · answered by Ivy 3 · 1⤊ 0⤋
If you sketch this on paper, you will have a right triangle whose base is 2.5 cm and altitude is 6 cm. apply the formula for a right triangle (a²+b²=c²) and you will get
(2.5cm)² + (6cm)² = L² = 6.25cm + 36 cm
L= the square root of 42.25 cm = 6.5 cm
2007-01-16 08:07:05 · answer #2 · answered by Marv 2 · 0⤊ 0⤋
Well from a cross-sectional point of view, surely this is just a case of "the square of the hypot is equal to the sum of the sqyares of the other two"
You have a right angle triangle here (upright / radius)
So: 2.5 x 2.5 + 6x6 then square root
6.25 + 36
42.25
SQR (42.25 = 6.5
2007-01-16 07:50:46 · answer #3 · answered by Mark T 6 · 2⤊ 0⤋
Use pythagorean theorem. Draw the picture, you'll see.
L^2 = r^2 + h^2.
2007-01-16 07:48:27 · answer #4 · answered by acafrao341 5 · 0⤊ 0⤋