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similar triangles

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49 articles trouvés pour ce sujet.
A trough with a triangular cross section 2016-05-21
Clarice pose la question :
A trough having an equilateral triangle end sections has sides equal to 0.4 m and 7m long.what is the volume of the liquid in the container if the depth of the water is one half the depth of the trough?
Penny Nom lui répond.
The angles of a triangle 2015-12-17
Faith pose la question :
Does the measure of angle determine the length of its side? For example two angles are congruent then the sides are also congruent because from my understanding the angle determine the shape of triangle.
Penny Nom lui répond.
The length of a shadow 2015-08-01
maaz pose la question :
I am having trouble with this question:

Lizzie, who is 6 feet tall, stands in her driveway at night, exactly 24 feet from the base of a spotlight, and casts a shadow that is 12 feet long if her friend Hannah who is 5 feet tall decides to stand next to lizzie how long will her shadow be?

Penny Nom lui répond.
A barge of triangular cross section 2014-08-18
tushar pose la question :
a barge of triangular cross section is 20m long 12 m wide and 6m deep.its floats in SW at a draft if 4m find its displacement
Penny Nom lui répond.
The length of a shadow 2014-05-09
vijay pose la question :
A girl of height 80 cm is running away from the base of a lamp-post at a speed of 2 m/s. If the lamp is 4 m above the ground, find the length of her shadow after 5 seconds.
Penny Nom lui répond.
Two cones 2014-04-09
c.j pose la question :
what is the length of the radius of the LARGER cone(the LARGER cone has a slant height of 15) when the SMALLER cone has a radius of 8 and a slant height of 12ft ,please help.
Penny Nom lui répond.
Shadows of a father and son 2014-04-02
esada pose la question :
the father and son cast a shadow of 11 feet and 8 feet,respectively if the son is 4'8'' in height,how tall is the father?
Penny Nom lui répond.
A triangle construction 2013-07-27
Nazrul pose la question :
Two angles and the difference of the lengths of their opposite sides of a triangle are given. How can I draw the triangle. Please help me.
Chris Fisher lui répond.
Calibrating a conical tank 2011-02-05
Bill pose la question :
Hi, I have a round tank with tapered sides where I know the diameter at the top and bottom. Is there a formula I can use to calculate the volume by measuring from the bottom up the side (at the angle of the side) to any given point? Thanks, Bill
Stephen La Rocque and Penny Nom lui répond.
The height of a lamp 2011-01-13
Dorothy pose la question :
I need to find the lamp height with casting shadow (base line of triangle where a boy 1.6m tall stands 3m from base of street lamp and has a 2m shadow. In other words, think of a right angle triangle with zero height starting at left, then 2m to right stands boy (1.6m high). Angle (hypotenuse) increases up to top of street lamp with 'x' height and 3m base.
Penny Nom lui répond.
The line through D(-4, 0) and E(2, 6) 2009-11-16
Rogerson pose la question :
The point F is on the line through D(-4, 0) and E(2, 6) so that DF=4DE. Find the coordinates of F.
Penny Nom lui répond.
A paper towel roll 2009-08-19
Jeff pose la question :
I am making a spiral tube with paper that is 2" in dia. and 102" long I will be using paper that is slit 3" wide how many lineal feet of paper will I need to to cover the 102" I will be using 3 rolls of paper that will over lap the other by half to make a hard tube (paper core) in a roll of paper towels Thanks Jeff
Penny Nom lui répond.
The position of the fulcrum 2009-05-23
jim pose la question :
I think I need a formula. I need to know how far an object will be lifted. A beam is 246 inches long on one side of the fulcrum, and 41 inches on the other side, if I push down 36 inches on the long side of the beam, how much will the short side move up?
Stephen La Rocque lui répond.
A 30-60-90 triangle 2009-02-03
Inez pose la question :
If you have a 30-60-90 triangle and the only side you get is 73 and a 90 degree box, how do you find the area?
Penny Nom lui répond.
The volume of a feed hopper 2008-12-18
John pose la question :
I need to calculate the volume of a feed hopper, and I'm not sure how to break it down. The top of the hopper is 36" x 36", it is 30" deep, and ends at a 6" x 6" plate. One side of the hopper is straight top to bottom, of course tapering on two sides to meet at the plate. The other three sides angle down at about 75 degrees. I need to determine the cubic foot volume of this hopper (it is used for ground coffee) so I can configure a vibrator to knock down residual grounds. Thanks.
Robert Dawson lui répond.
3 equidistant points 2008-12-01
Damien pose la question :
How do you find 3 equidistant points (C,D,E) on a line between point A(Xa, Ya) and point B(Xb, Yb) so that AC, CD, DE and EB are all equal?
Chris Fisher lui répond.
The midpoint o a line segment 2008-11-15
Jane pose la question :
The vertices of a triangle are at (1,7), (6,-1) and (0,3). Find the coordinates of the midpoints of the sides.
Penny Nom lui répond.
A flagpole and a yardstick 2008-11-07
Wanda pose la question :
One boy holds a yardstick vertically at a point 40 feet from the base of the flagpole. The other boy backs away from the pole to a point where he sights the top of the pole over the top of the yardstick. If his position is 1 ft 9 in from the yardstick and his eye level is 2 ft above the ground, find the height of the flagpole.
Penny Nom lui répond.
Similar Triangles Given a Median 2008-08-17
RAM pose la question :
Sides AB , AC and median AD of a triangle ABC are respectively proportional to PQ PR and median PM of another triangle PQR. Show that ABC is similar to PQR
Janice Cotcher lui répond.
Similar triangles 2008-08-12
ramarao pose la question :
D is a point on side BC of a triangle ABC such that BD/CD=AB/AC. prove that AD is the bisector AD is the bisector of BAC
Chris Fisher lui répond.
Similar triangles 2008-03-26
Nisha pose la question :
In triangle ABC, LM is parallel to AB. If AL=x-3,AC=2x,BM=x-2,BC=2x=3. Find x
Penny Nom lui répond.
A flagpole and a statue 2008-02-09
Krista pose la question :
A flagpole casts a ten meter (m) shadow at the same time as a six metre (m) statute beside it casts a two metre shadow. What is the height of the flagpole??
Steve La Rocque and Penny Nom lui répond.
Forces on an inclined plane 2008-01-10
Ron pose la question :
A body that weighs 540lbs is caused to slide up an inclined plane with a uniform velocity by a force that acts parallel to the plane. For each foot of horizontal distance, there is a vertical rise of 2in. If the coefficient of sliding friction is 0.16, what force is required to move the body?
Stephen La Rocque lui répond.
Lining up coins visually using geometry and trigonometry 2007-12-31
Jessica pose la question :
a) In what order would you arrange a penny, a nickel, a dime, a quarter, and a half-dollar so that they all have the same apparent size? The diameters of the coins, in thousandths of inches, are as follows: penny, 750; nickel, 835; dime, 705; quarter, 955; half-dollar, 1205.
b) How should the coins be placed, if the distance between the dime and the half-dollar is 100 units? How far from thw dime should your eye be to see that all the coins have the same apparent size?
c) What angle do the coins subtend when they have the same apparent size?

Stephen La Rocque lui répond.
Smallest cone containing a 4cm radius inscribed sphere 2007-12-19
Eva pose la question :
A sphere with a radius of 4cm is inscribed into a cone. Find the minimum volume of the cone.
Stephen La Rocque lui répond.
Related Rates (streetlamp and shadow) 2007-11-09
Casey pose la question :
A street light is mounted at the top of a 15ft pole. A man 6ft tall walks away from the pole at a rate of 5ft per second. How fast is the tip of his shadow moving when he is 40ft from the pole?
Stephen La Rocque and Penny Nom lui répond.
Surface area of an open-ended cone 2007-10-16
Lorne pose la question :
What is the surface area of an open ended cone? Measured at 10' high, 16' diameter on the bottom and 2' diameter at the top.
Stephen La Rocque lui répond.
Similar triangles 2007-08-29
James pose la question :
Question: In the triangle ABC, X is a point on AC. AX = 15 m and XC = 5 m. The angle AXB is 60 degrees and the angle ABC is 120 degrees. Find the length of BC.

I am sure to an extent that this has to do with similar triangles, but I am not certain.

Harley Weston lui répond.
Volume in a triangular water trough 2007-06-24
David pose la question :
A water trough has sloping sides of length 500mm making it triangular in cross section, with vertical ends. The width at the top is 600mm and the length is 2.0 metres.
(i) Calculate the capacity of the trough, giving your answer accurate to the nearest litre.
(ii) Find out the depth of the water when the trough is half full.

Stephen La Rocque lui répond.
Similar triangles 2007-02-21
Vivienne pose la question :
The lengths of the sides of a triangle are 8, 15, & 17. If the longest side of a simlar triangle is 51, what is the length of the shortest side?
Stephen La Rocque and Penny Nom lui répond.
Height of a right triangle? 2007-01-29
Engelbert pose la question :
The base of the right triangle is 50 ft. At the angle (on the base of the triangle) across from the right angle is labeled portion (a triangle within a triangle), the base of this little triangle is 10 ft. and the height is 6 ft. What equation can i use to solve this?
Steve La Rocque and Haley Ess lui répond.
In the shadow of a building 2007-01-11
Bill pose la question :
if a building b feet cast a shadow f feet long, then, at the same time of the day, a tree t feet high will cast a shadow, how many feet long?
Stephen La Rocque lui répond.
How do the perimeters of the two pentagons compare? 2007-01-02
Robert pose la question :
If the area of one pentagon is eighty-one times the area of another pentagon, how do the perimeters of the two pentagons compare?
Penny Nom lui répond.
The height of a building 2006-11-19
Sweetie pose la question :
I have to figure out the measure of the water towers antenna on my schools campus using up to two items created by me and a manual. I don't know far away we are going to have to be. I need to have a fool proof way to figure out the distance to the tower. I have an idea using trigonometry but its really roughly estimated. Do you have any suggestions?
Stephen La Rocque lui répond.
How fast is the water level rising 2006-08-12
Erin pose la question :
Water runs into a conical tank at the rate of 9ft3/min. The tank stands point down and has a height of 10 ft. and a base radius of 5 ft. How fast is the water level rising when the water is 6 ft. deep? (V=1/3 pi r2 h).
Penny Nom lui répond.
Designing a garage 2006-06-08
A builder pose la question :
I'm currently designing a garage and came upon this interesting math problem. I've tried using various methods to solve it but have so far been unsuccessful. I've included a picture as its far easier to show you my question than explain it verbally. I realize it could be done by trial and error but i'm looking for a real solution.
Stephen La Rocque and Penny Nom lui répond.
The volume of water in a cone 2006-03-21
Ghulam pose la question :
A vessel has the shape of an inverted cone.The radius of the top is 8 cm and the height is 20 cm. Water is poured in to a height of x cm.Show that if the volume of the water is V cubic cm,then V=(4/75)pi x3.
Penny Nom lui répond.
Heights and shadows 2006-03-06
Debra pose la question :
A person is 7 ft tall and his shadow is 10 ft tall. using the same info what is the shadow of a person who is 5ft tall
Stephen La Rocque lui répond.
Water in a cone 2004-07-28
A student pose la question :
A vertically inverted cone( i.e. vertex down) has a radius 7 inches and height 24 inches. Water is filled to one third of its height .Find the ht of water when cone is turned upside down
Penny Nom lui répond.
A geometry problem 2004-03-04
Jennifer pose la question :
I need help with this problem: Square ABCD has side length 2. A semicircle with diameter AB is constructed inside the square, and the tangent to the semicircle from C intersects side AD at E. What is the exact length of CE?o
Chris Fisher lui répond.
Two chords 2003-10-07
Lori pose la question :
Chords AB and CD of circle O intersect at E. If AE=4, AB=5, CE=2, Find ED.
Penny Nom lui répond.
Water in a cone 2003-08-12
Adrienne pose la question :

Water is poured into a tank in the shape of an inverted right circular cone.ð The height of the tank is 8 m and its radius at the top is 4 m.

a. Draw and label a picture to represent this situation.ð (I know how to do this)

b. Identify all variable quantities. (h = 8m, r = 4m)

c. Find an equation that relates the variable quantities, and reduce the number of variable quantities to two.

I was thinking about the equation V = 1/3 pi r2 h, which is the Volume of a cone, but I am stumped as to how I am supposed to "reduce the number of variable quantities to two." Can you point me in the right direction?

Penny Nom lui répond.
Similar triangles 2001-09-08
Dave pose la question :
I am standing on the bank of a river ( whose banks are parallel here) directly opposite a boathouse, B, on the opposite bank. I walk along the bank of the river past a signpost, S, until I reach a point C distant 60 metres from where I started walking. I then walk away from the bank, at right angles to the bank, until I reach a shady tree at D. Attached to teh tree is a sign stating that this spot is 45 metres from the signpost. C is 36 metres beyond S and B and S are in line from D.

(a) How far did I walk away from the bank of the river??

(b) Calculate the width of the river?

Penny Nom lui répond.
How tall is the tree? 2001-03-02
Ronda pose la question :
a tree's shadow is 42 ft. long. There is a stop sign that is right next to it and it is 18 ft. tall and it's shadow is 12 ft. long. How tall is the tree?
Penny Nom lui répond.
A lampost and its shadow 2000-12-24
Laura pose la question :
A lamppost line EC casts a shadow line AC. A 30 cm ruler line DB has been moved from A so that it's shadow falls just within the shadow of the lamppost.
  1. Suppose the length of the ruler's shadow is 42 cm. What is the slope of the imaginary line AE?

  2. Suppose the lamppost's shadow is 15 m. long. How tall is the lamppost?

Penny Nom lui répond.
Length of a shadow 2000-11-01
Jessy pose la question :
A man who is six feet tall is walking away from a street light that is fifteen feet tall. How long is the man's shadow when he is ten feet away from the light?
Penny Nom lui répond.
Two 12-sided polygons 1999-09-25
Kelly Boulton pose la question :
Two 12-sided polygons are similar. A side of the larger polygon is 3 times as long as the corresponding side of the smaller polygon. wHAT IS the ratio of the area of the larger polygon to the area of the smaller polygon.
Walter Whiteley lui répond.
A ladder problem 1999-04-22
Michael Blade pose la question :
There is a cube box 3feet x 3feet x 3ft resting against a vertical wall on level ground. Resting against the outside corner of the box is a ladder 10 feet tall, this ladder is of course resting on the ground but also against the outside corner of the box and rests on the wall.

The question- the ladder is divided into two unequal section bounded by the box to the ground and the box to the wall. what are those dimensions?
Penny Nom lui répond.

Shimin's Geometry Problem 1997-12-02
Ong Shimin pose la question :
ABCD is a rectangle. X and Y are the midpoints of BC and CD respectively. W is a point on AB such that AW : WB = 2 : 1. Z is a point on AD such that AZ : ZD = 2 : 1.

WY intersects XZ at O. If the area of triangle WOZ is 84 centimeters squared, find the area of triangle XOY.
Chris Fisher lui répond.




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