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Category: Geometry

The-distances-from-a-point-to-the-sides-of-a-triangle-are-p-q-r-Find-the-maximum-or-minimum-area-of-the-triangle-if-it-exists-Assume-r-q-p-

Question Number 50352 by mr W last updated on 16/Dec/18 $${The}\:{distances}\:{from}\:{a}\:{point}\:{to}\:{the}\:{sides} \\ $$$${of}\:{a}\:{triangle}\:{are}\:{p},{q},{r}.\:{Find}\:{the}\: \\ $$$${maximum}\:\left({or}\:{minimum}\right)\:{area}\:{of}\:{the} \\ $$$${triangle},\:{if}\:{it}\:{exists}. \\ $$$${Assume}\:{r}\leqslant{q}\leqslant{p}. \\ $$ Commented by ajfour last…

Question-181232

Question Number 181232 by mr W last updated on 23/Nov/22 Commented by mr W last updated on 23/Nov/22 $${a}\:{train}\:{drives}\:{from}\:{A}\:{in}\:{direction}\:{to} \\ $$$${D}\:{with}\:{speed}\:\mathrm{160}\:{km}/{h}.\:{at}\:{the}\:{same} \\ $$$${time}\:{a}\:{car}\:{drives}\:{from}\:{B}\:{in}\:{direction} \\ $$$${to}\:{E}\:{with}\:{speed}\:\mathrm{100}\:{km}/{h}.…

Question-181201

Question Number 181201 by HeferH last updated on 22/Nov/22 Answered by ARUNG_Brandon_MBU last updated on 23/Nov/22 $$\mathrm{tan}\theta=\frac{\mathrm{3}}{\mathrm{4}} \\ $$$$\mathrm{tan2}\theta=\frac{\frac{\mathrm{3}}{\mathrm{4}}+\frac{\mathrm{3}}{\mathrm{4}}}{\mathrm{1}−\frac{\mathrm{3}}{\mathrm{4}}\centerdot\frac{\mathrm{3}}{\mathrm{4}}}=\frac{\mathrm{24}}{\mathrm{7}}=\frac{{AC}}{{AE}}=\frac{{AC}}{\mathrm{4}} \\ $$$$\Rightarrow{AC}=\frac{\mathrm{96}}{\mathrm{7}} \\ $$$$\mathrm{area}\left({ABC}\right)=\frac{\mathrm{1}}{\mathrm{2}}×{AB}×{AC} \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:=\frac{\mathrm{1}}{\mathrm{2}}×\mathrm{9}×\frac{\mathrm{96}}{\mathrm{7}}=\frac{\mathrm{432}}{\mathrm{7}}…

A-vertical-post-of-height-h-m-rises-from-a-plane-which-slopes-down-towards-the-South-at-an-angle-to-the-horizontal-Prove-that-the-length-of-its-shadow-when-the-sun-is-S-W-at-an-elevation-is-

Question Number 115642 by 24224 Opiyo Kamuki last updated on 27/Sep/20 $${A}\:{vertical}\:{post}\:{of}\:{height}\:{h}\:{m}\:{rises}\:{from}\:{a}\:{plane}\:{which}\: \\ $$$${slopes}\:{down}\:{towards}\:{the}\:{South}\:{at}\:{an}\:{angle} \\ $$$$\alpha\:{to}\:{the}\:{horizontal}.\:{Prove}\:{that}\:{the}\:{length} \\ $$$${of}\:{its}\:{shadow}\:{when}\:{the}\:{sun}\:{is}\:\boldsymbol{{S}\theta{W}}\:\: \\ $$$${at}\:{an}\:{elevation}\:\beta\:{is} \\ $$$$ \\ $$$$\frac{{h}\sqrt{\left(\mathrm{1}+{tan}^{\mathrm{2}} \alpha\:{cos}^{\mathrm{2}}…

Let-the-acute-triangle-ABC-have-an-outer-circumscribed-circle-whose-tangents-at-the-points-B-and-C-intersect-at-point-P-Let-D-and-E-be-the-projections-of-perpendicular-lines-from-point-P-on-AC-and

Question Number 181125 by depressiveshrek last updated on 21/Nov/22 $${Let}\:{the}\:{acute}\:{triangle}\:\Delta{ABC}\:\:{have} \\ $$$${an}\:{outer}\:{circumscribed}\:{circle}, \\ $$$${whose}\:{tangents}\:{at}\:{the}\:{points}\:{B}\:{and}\:{C} \\ $$$${intersect}\:{at}\:{point}\:{P}.\:{Let}\:{D}\:{and}\:{E}\:{be} \\ $$$${the}\:{projections}\:{of}\:{perpendicular} \\ $$$${lines}\:{from}\:{point}\:{P}\:{on}\:{AC}\:{and}\:{AB}. \\ $$$${Prove}\:{that}\:{the}\:{interdection}\:{point}\:{of} \\ $$$${the}\:{heights}\:{of}\:\Delta{ADE}\:{is}\:{the}\:{midpoint} \\…