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Proof: ca=co
am=mocm⊥ab
In a right-angled triangle BMC.
pb=pcpm=1 2bc (the right triangle hypotenuse is the middle line equal to half the length of the hypotenuse) The same is true. In a right-angled triangle BNC.
pn=1/2bc
pm=pn
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You can get 2 points, and you will get bounty points and 20 points
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Geometry problems with affection? What do you mean?
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Connect to the IO, IP, and ID
Easy Evidence POI DOI
The radius of the circumscribed circle of the doi is the same as the radius of the circumscribed circle of the poi, and op 6, pio 90° 1 2 pqo 135° is the diameter of the circumscribed circle of the pio, so the poc is an isosceles right triangle pc 2op 6 2
Thus the radius of the doi is 3 2 choose d
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You do it right, turn the original diagram into a square, you can find ae as two times the root number six, the diagonal is twice the root number of the side length, ac = four times the root number two.
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(1)∵bc‖do
Angular CBA = Angular DOA
and d= bac
Angular CBA+ D = Angular DOA+ BAC
That is, angular bac = angular dao = 90°
Ad is the tangent of a semicircle o.
2) 3 roots of 10
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(1) d= bac, doa= abc, acb=90°, dao=90°, proven.
2) From (1), we know that the two large triangles are similar, and both are similar to AEO, BC:OE = AE:AC, AE:AD=OE:OA, and it is easy to know AE=3, OE=1, OA= 10 from the known conditions
ae:ad=oe:oa,,3:ad=1:√10,ad=3√10
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1、∵od‖bc,∴∠doa=∠cba
d= bac, bca= dao, and abc doa and bca=90°, dao=90°, so ad is the tangent of the semicircle o.
2. According to the similarity theorem, know abc aeo
oa ab = ae ac=1 2, get ac = 6 ab = ac2 + bc2 = 2 10, oa = 10, bc oa = ac ad, ad=3 10
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∵bc//od∴∠cba=∠doa
and d= bac dao= bca=90° ad is the tangent of the semicircle o.
bc ac=ao ad=ab 2ad ae oe=ac bc oe ao=ae ad solution equation.
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Solution: (1) Proof of: d= bac
Whereas, BC OD then CBA= AOD
abc∽△ doa
And acb is the angle of the diameter of the semicircle o, then acb=90° then acb= doa=90°, i.e., ad ab
Ad is the tangent of a semicircle o.
2) BC OD is easy to know AOE ABC
Therefore, ae ac=ao ab=1 2 gives ac=2ce=6ao=1 2 (|bc|²+ac|) = 10 from (1) abc doa
ad/ac=ao/bc
Get ad=3 10
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Obviously, the area of the triangle dam is 1 4
Obviously, the triangular EBM is similar to the triangular EDC, and the chain pin MB=CD2, so the area of the triangular EDC is 4 times that of the triangular EMB.
Let the area of the triangle EMB be X, then the area of the triangle EDC is 4X, and the area of the triangle DMB is 1 4, and the area of the triangle MCD is 1 2, and let the surface of the triangle MDE be Y, then:
x+y=1/4, 4x+ y = 1/2
The solution is x=1 12 y= 1 6
The triangle MBC area is 1 4, so the triangle EBC area = 1 4 - 1 12 = 1 6 and the last black part area is 1 6 + 1 6 = 1 3
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Before I took it, there were 8 that took A, B, and C, and after that, there were still only 8.
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8 There are 3 faces on each corner of each corner for a total of 8 corners.
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Because :,ad bc, the isotope angles are equal, b= ead=30° bad=180- ead=150°
AD is the bisector of EAC, EAC=2* EAD=60°
Angular BAC = 180- EAC = 120°
Angle c = 180-30-120 = 30°
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∠ead=∠b=30°
eac=2∠ead=60°
Angle BAC = 180 degrees - Angle EAC = 120 degrees.
Angle c = 180 degrees, minus angle B, subtracted angle BAC is equal to 30 degrees.
The angle bad is equal to the angle BAC + the angle DAC is equal to 150 degrees. or angle BAD = 180 degrees minus angle EAD = 150 degrees.
I hope you can understand the Chinese characters in the back.
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∵∠b+∠bac+∠c=180°
again a=90°
c=180°-90°-30°=60°
eac=90°
eac=90°
ead=90°÷2=45°
dac=45° ,bad=90°+45°=135° and then modify it.
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Because AD is parallel to BC, the angle EAD is 30, BAD is 150, EAC is 60, and C is 30
The simplest solution: when a, e overlap, f, b overlap, and the conditions given by the problem are satisfied, then edf= adb=45°
As shown in the figure: let the center of the circle be the coordinate point and the radius is 2 [this is to calculate the coordinates of e, b, f, h, and then find the equation of a circle according to the coordinates of bfh, if it can be done, you can prove that the three-point bfh is coherent, and then bring the coordinates of e into the same equation, if it conforms to the relation, then the four-point ebfh four-point contour] So e(o,o) b(root number 2, root number 2) f(-root number 2, 3 root number 2) [The coordinates of f can first find the intersection point P of the y-axis and bf, according to p, b two points to find the straight line, so as to get the y value of f. See below for details: >>>More
In this text, (bac) (acd) is used instead of angangle bac and acd >>>More
By the inscription: a + c + 1 = 180°
a+∠d+∠2=180° >>>More
Even oo', then boo' is a regular triangle, and aoo' is a right-angled triangle with three sides, and the area of the quadrilateral ao'bo is 4 3+6. Similarly, turn OC 60 degrees clockwise, and then connect AO'' to get a side length of 5 regular triangles and right triangles, with an area of (25 roots, numbers, 3) 4+6, and the same AO turns 60 degrees to obtain quadrilaterals (9 roots, numbers, 3) 4+6 >>>More