Find a ratio of triangle's height segment
$begingroup$
Given a right angle triangle ABC
(C = 90) and a median AM
. CD
is the height of the triangle and it intersects median in point K
. What is the CK / KD
ratio?
geometry euclidean-geometry triangle ratio
$endgroup$
add a comment |
$begingroup$
Given a right angle triangle ABC
(C = 90) and a median AM
. CD
is the height of the triangle and it intersects median in point K
. What is the CK / KD
ratio?
geometry euclidean-geometry triangle ratio
$endgroup$
add a comment |
$begingroup$
Given a right angle triangle ABC
(C = 90) and a median AM
. CD
is the height of the triangle and it intersects median in point K
. What is the CK / KD
ratio?
geometry euclidean-geometry triangle ratio
$endgroup$
Given a right angle triangle ABC
(C = 90) and a median AM
. CD
is the height of the triangle and it intersects median in point K
. What is the CK / KD
ratio?
geometry euclidean-geometry triangle ratio
geometry euclidean-geometry triangle ratio
asked Jan 14 at 17:18
Most WantedMost Wanted
1156
1156
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
$begingroup$
Let $AC=b$, $BC=a$ and $N$ be placed on $DB$ such that $MNperp AB.$
Thus, $$MN=frac{1}{2}CD,$$
$$AD=frac{b^2}{sqrt{a^2+b^2}}$$ and
$$BD=frac{a^2}{sqrt{a^2+b^2}}.$$
Id est, $$frac{KD}{MN}=frac{AD}{AN}=frac{frac{b^2}{sqrt{a^2+b^2}}}{frac{b^2}{sqrt{a^2+b^2}}+frac{a^2}{2sqrt{a^2+b^2}}}=frac{2b^2}{a^2+2b^2}.$$
Thus, $$frac{KD}{CD}=frac{b^2}{a^2+2b^2}$$ or
$$frac{CD}{KD}=frac{a^2+2b^2}{b^2}$$ or
$$1+frac{CK}{KD}=frac{a^2+b^2}{b^2}+1,$$ which gives
$$CK:KD=(a^2+b^2):b^2.$$
We see that the needed ratio depends on the ratio $a:b$.
$endgroup$
$begingroup$
Thanks a lot, but could you explain the part where you come up with KD to MN ratio, see my answer below.
$endgroup$
– Most Wanted
Jan 14 at 20:28
add a comment |
$begingroup$
I have a different answer
$$ frac{CK}{KD} = frac{a-b}{b} $$
so I want to clarify: how did you conclude that
$$ MN = frac{b^2}{sqrt{a^2+b^2}} + frac{a^2}{2sqrt{a^2+b^2}}$$
I have MN
equals to $ frac{ab}{2sqrt{a^2+b^2}}$
$endgroup$
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3073481%2ffind-a-ratio-of-triangles-height-segment%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Let $AC=b$, $BC=a$ and $N$ be placed on $DB$ such that $MNperp AB.$
Thus, $$MN=frac{1}{2}CD,$$
$$AD=frac{b^2}{sqrt{a^2+b^2}}$$ and
$$BD=frac{a^2}{sqrt{a^2+b^2}}.$$
Id est, $$frac{KD}{MN}=frac{AD}{AN}=frac{frac{b^2}{sqrt{a^2+b^2}}}{frac{b^2}{sqrt{a^2+b^2}}+frac{a^2}{2sqrt{a^2+b^2}}}=frac{2b^2}{a^2+2b^2}.$$
Thus, $$frac{KD}{CD}=frac{b^2}{a^2+2b^2}$$ or
$$frac{CD}{KD}=frac{a^2+2b^2}{b^2}$$ or
$$1+frac{CK}{KD}=frac{a^2+b^2}{b^2}+1,$$ which gives
$$CK:KD=(a^2+b^2):b^2.$$
We see that the needed ratio depends on the ratio $a:b$.
$endgroup$
$begingroup$
Thanks a lot, but could you explain the part where you come up with KD to MN ratio, see my answer below.
$endgroup$
– Most Wanted
Jan 14 at 20:28
add a comment |
$begingroup$
Let $AC=b$, $BC=a$ and $N$ be placed on $DB$ such that $MNperp AB.$
Thus, $$MN=frac{1}{2}CD,$$
$$AD=frac{b^2}{sqrt{a^2+b^2}}$$ and
$$BD=frac{a^2}{sqrt{a^2+b^2}}.$$
Id est, $$frac{KD}{MN}=frac{AD}{AN}=frac{frac{b^2}{sqrt{a^2+b^2}}}{frac{b^2}{sqrt{a^2+b^2}}+frac{a^2}{2sqrt{a^2+b^2}}}=frac{2b^2}{a^2+2b^2}.$$
Thus, $$frac{KD}{CD}=frac{b^2}{a^2+2b^2}$$ or
$$frac{CD}{KD}=frac{a^2+2b^2}{b^2}$$ or
$$1+frac{CK}{KD}=frac{a^2+b^2}{b^2}+1,$$ which gives
$$CK:KD=(a^2+b^2):b^2.$$
We see that the needed ratio depends on the ratio $a:b$.
$endgroup$
$begingroup$
Thanks a lot, but could you explain the part where you come up with KD to MN ratio, see my answer below.
$endgroup$
– Most Wanted
Jan 14 at 20:28
add a comment |
$begingroup$
Let $AC=b$, $BC=a$ and $N$ be placed on $DB$ such that $MNperp AB.$
Thus, $$MN=frac{1}{2}CD,$$
$$AD=frac{b^2}{sqrt{a^2+b^2}}$$ and
$$BD=frac{a^2}{sqrt{a^2+b^2}}.$$
Id est, $$frac{KD}{MN}=frac{AD}{AN}=frac{frac{b^2}{sqrt{a^2+b^2}}}{frac{b^2}{sqrt{a^2+b^2}}+frac{a^2}{2sqrt{a^2+b^2}}}=frac{2b^2}{a^2+2b^2}.$$
Thus, $$frac{KD}{CD}=frac{b^2}{a^2+2b^2}$$ or
$$frac{CD}{KD}=frac{a^2+2b^2}{b^2}$$ or
$$1+frac{CK}{KD}=frac{a^2+b^2}{b^2}+1,$$ which gives
$$CK:KD=(a^2+b^2):b^2.$$
We see that the needed ratio depends on the ratio $a:b$.
$endgroup$
Let $AC=b$, $BC=a$ and $N$ be placed on $DB$ such that $MNperp AB.$
Thus, $$MN=frac{1}{2}CD,$$
$$AD=frac{b^2}{sqrt{a^2+b^2}}$$ and
$$BD=frac{a^2}{sqrt{a^2+b^2}}.$$
Id est, $$frac{KD}{MN}=frac{AD}{AN}=frac{frac{b^2}{sqrt{a^2+b^2}}}{frac{b^2}{sqrt{a^2+b^2}}+frac{a^2}{2sqrt{a^2+b^2}}}=frac{2b^2}{a^2+2b^2}.$$
Thus, $$frac{KD}{CD}=frac{b^2}{a^2+2b^2}$$ or
$$frac{CD}{KD}=frac{a^2+2b^2}{b^2}$$ or
$$1+frac{CK}{KD}=frac{a^2+b^2}{b^2}+1,$$ which gives
$$CK:KD=(a^2+b^2):b^2.$$
We see that the needed ratio depends on the ratio $a:b$.
answered Jan 14 at 18:21
Michael RozenbergMichael Rozenberg
103k1891196
103k1891196
$begingroup$
Thanks a lot, but could you explain the part where you come up with KD to MN ratio, see my answer below.
$endgroup$
– Most Wanted
Jan 14 at 20:28
add a comment |
$begingroup$
Thanks a lot, but could you explain the part where you come up with KD to MN ratio, see my answer below.
$endgroup$
– Most Wanted
Jan 14 at 20:28
$begingroup$
Thanks a lot, but could you explain the part where you come up with KD to MN ratio, see my answer below.
$endgroup$
– Most Wanted
Jan 14 at 20:28
$begingroup$
Thanks a lot, but could you explain the part where you come up with KD to MN ratio, see my answer below.
$endgroup$
– Most Wanted
Jan 14 at 20:28
add a comment |
$begingroup$
I have a different answer
$$ frac{CK}{KD} = frac{a-b}{b} $$
so I want to clarify: how did you conclude that
$$ MN = frac{b^2}{sqrt{a^2+b^2}} + frac{a^2}{2sqrt{a^2+b^2}}$$
I have MN
equals to $ frac{ab}{2sqrt{a^2+b^2}}$
$endgroup$
add a comment |
$begingroup$
I have a different answer
$$ frac{CK}{KD} = frac{a-b}{b} $$
so I want to clarify: how did you conclude that
$$ MN = frac{b^2}{sqrt{a^2+b^2}} + frac{a^2}{2sqrt{a^2+b^2}}$$
I have MN
equals to $ frac{ab}{2sqrt{a^2+b^2}}$
$endgroup$
add a comment |
$begingroup$
I have a different answer
$$ frac{CK}{KD} = frac{a-b}{b} $$
so I want to clarify: how did you conclude that
$$ MN = frac{b^2}{sqrt{a^2+b^2}} + frac{a^2}{2sqrt{a^2+b^2}}$$
I have MN
equals to $ frac{ab}{2sqrt{a^2+b^2}}$
$endgroup$
I have a different answer
$$ frac{CK}{KD} = frac{a-b}{b} $$
so I want to clarify: how did you conclude that
$$ MN = frac{b^2}{sqrt{a^2+b^2}} + frac{a^2}{2sqrt{a^2+b^2}}$$
I have MN
equals to $ frac{ab}{2sqrt{a^2+b^2}}$
answered Jan 14 at 20:26
Most WantedMost Wanted
1156
1156
add a comment |
add a comment |
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3073481%2ffind-a-ratio-of-triangles-height-segment%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown