Urgent: Basic Trigonometry

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other-side-of-d-moon

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Hello Guys

could you please help me to find the hypotenuse for the red triangle please.




regards
 

yes and no... small and large hypot. ratios equal side ratios and opposite ratio.. then solve. for unknown h

then square of h= square of opposite + square of adjacent side is extra equation..when needed . then sub. result of one equation into the rest untill you have only h=....
https://en.wikipedia.org/wiki/Hypotenuse#Calculating_the_hypotenuse
 


Hello,

You mention "red triangle", but what I see isn't a triangle. As you don't know the vertical heigth of the red figure, you can't calculate the hypotenuse of it. So you need more information.

You can calculate it for the top triangle with h = 3, using ratio's as suggested by SunnySkyGuy, and Pythagoras
 

Ooooo kayyy the simple answer is 2.5

Why
See the 3x4 triangle? the red and white part above it

guess what? 3x4x5 triangle is a standard value. in right angle triangles 3^2+4^2=5^2

so if the red part is splits the the hypotenuse dimension {5) along the edge ( big assumption since not stated)

then it must be 1/2 of 5 = 2.5 if split equal.
but guess what? tangent (3/4) in radians is not 40deg.. trick question...

and

if that triangle is 3x4 (h=5) then the bigger triangle 5x6 is wrong since the ratios do not match
and the biggest triangle 8 x10 also does not match the 3x4 ratio..
in fact none of the 3 triangles have the proper dimension or angle of 40deg...

You've been tricked... and you are supposed to see that....in a few seconds...
 

yes, if you calculate the area of the whole figure and then calculate the area from the 'little parts' it does not match
something is wrong by accident or on purpose
 

It is pellucidly obvious that the problem of solving for the red area cannot be solved with the information given. The bounding top line is not defined.

John
 

Cannot be solved with given info. Convince yourself by imagining the top triangle is a fluid tank and the red section is the amount of fluid in the tank. You can change it by adding or removing fluid changing the top line of the red section without any of the given numbers changing.

If they gave you info on one more of the red section sides, one more side of the top unfilled section triangle, the area of the very top unfilled triangle, or area of red section then it could be solved.

One subtle pre-requisite given one additional piece of info mentioned above, is you need to first prove it forms a right triangle using the 40 degs and the other bottom given dimensions.

In this the full outline does not match up. Squareroot of [(6+4)^2 + (5+3)^2] = 12.8062 which is the full outside hypot. sin(40 degs) x 12.8062 = 8.23 which is not exactly equal the 5 + 3 vertical side.
 
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just asking, lets say the given info was different, the same info just other 'matching' numbers.
then you would be able to solve right ?
 

You mention "red triangle", but what I see isn't a triangle.
Click to expand...
Perhaps the original question is: "Explain the difference between a triangle and a quadrangle"?

Ooooo kayyy the simple answer is 2.5
Click to expand...
At least it's the best guess.
 

Changing the numbers won't help. The red shape still isn't a triangle, and there's no info on the height of it.
 

sorry, you're right

it would need at least any info on the red shape. base or area or any other
 

it looks like a good interview question to see the analytical skills of understanding the question gives erroneous data, which many should recognize and happens frequently in many forums. Testing the known data verifies that the assumptions are false.

For example the angle is given of 40 deg while the opposite and adjacent lengths add up to 8 and 10, and we know Tan (ø) =(8/10
If the tangent ratio of 0.80000000000000
and the tan (40 deg ) = 0.83909963117728, then the assumption that valid data was given is proven false.
 

Fully pedantic mode is [ON].

There's a red triangle hidden conveniently within that red polygon up there. So we'll use that triangle as "the red triangle". And given the provided information, for the hypothenuse of that triangle we can give an upper and a lower bound, and that's it. The end. neeeext.
 

Ambiguous questions deserve succinct answers.

This question is a good example. The intent is to confuse you to thinking there is a rational answer, which there is not.
the length along the hypotenuse with "??" beside it implies this is the question they are asking that intersects with the red area within the large triangle. But even ancient Egyptians would say they cubits of measure do not add up.
 

I love questions like this. You can make stuff up as you go along and you can still make it fit the requirements.
 

wow awesome a lil mis post creating a lot of idea spree that is math any way

other-side-of-d-moon pls don't take us there it is really dark with your post
 

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