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How to do this eighth grade math problem?
Test center: congruent triangles's judgment; Coordinate and graphic attributes; Properties of isosceles triangle.

Special topic: computational problems; Query type.

Analysis: (1) Because △AOB is an isosceles right triangle and A (4 4,4) is AE⊥OB in E, the coordinates of point B can be obtained;

(2) Let AE⊥OB be in E, DF⊥OB be in F, and verify △ DFC △ CEA. Then, according to the equivalent transformation, it is proved that △AOB is an isosceles right triangle, and then the degree of △ ∠AOD can be obtained;

(3) The equation holds. It is easy to prove △EAN≌△AE⊥OB by intercepting AN=OF, even en. Then it is proved that △ nem △ FEM has AM-MF=OF according to the angle relation, and the equation is established. Solution: (1)

∫A(4,4),

∴OE=4,

∵△AOB is an isosceles right triangle, while AE⊥OB,

∴OE=EB=4,

∴OB=8,

∴b(8,0);

(2) Let AE⊥OB be in E, DF⊥OB be in F,

△ ACD is an isosceles right triangle,

∴AC=DC,∠ACD=90

That is, < ACF+< DCF = 90,

∫∠FDC+∠DCF = 90,

∴∠ACF=∠FDC,

∠∠DFC =∠AEC = 90,

∴△DFC≌△CEA,

∴EC=DF,FC=AE,

∫A(4,4),

∴AE=OE=4,

∴FC=OE, that is, +EF=CE+EF,

∴OF=CE,

∴OF=DF,

∴∠DOF=45,

∫△AOB is an isosceles right triangle,

∴∠AOB=45,

∴∠aod=∠aob+∠dof=90;

Method 1: the extension line of CK⊥x axis intersecting OA is at K,

Then △OCK is an isosceles right triangle, OC=CK, ∠ k = 45,

∫△ACD is isosceles Rt△,

∴∠ACK=90 -∠OCA=∠DCO,AC=DC,

∴△ACK≌△DCO(SAS),

∴∠DOC=∠K=45,

∴∠aod=∠aob+∠doc=90;

(3) (AM-MF)/OF= 1 is established for the following reasons:

Intercept AN=OF, even en on AM.

∫A(4,4),

∴AE=OE=4,

∵∠ ean =∠ eof = 90,AN=OF,

∴△EAN≌△EOF(SAS),

∴∠OEF=∠AEN,EF=EN,

And ∵△EGH are isosceles right triangles,

Geh = 45, that is, OEF+OEM = 45,

∴∠AEN+∠OEM=45

∫∠AEO = 90 degrees,

∴∠NEM=45 =∠FEM,

EM = EM once again,

∴△NEM≌△FEM(SAS),

∴MN=MF,

∴AM-MF=AM-MN=AN,

∴AM-MF=OF,

Namely (am-MF)/of =1;

Method 2: intercept ON=AM, EN, MN,

Then △ EAM △ eon (SAS), EN=EM, ∠NEO=∠MEA,

That is, ∠NEF+∠FEO=∠MEA, and ∠ MEA+∠ MEO = 90,

∴∠ NEF+∠ FeO+∠ MEO = 90, while ∠ FeO+∠ MEO = 45,

∴∠nef=45 =∠mef,∴△nef≌△mef(sas),∴nf=mf,

∴AM=OF=OF+NF=OF+MF, that is, (am-MF)/of = 1.

(1) is the 2B point coordinate of your problem, and (2) is the AOD degree of your problem 1. Ask me if you don't understand.

I have done this problem, and there is another 1 answer.

Title: As shown in the figure, in the plane rectangular coordinate system, △AOB is an isosceles right triangle, A (4 4,4).

(1) Find the coordinates of point B;

(2) If C is the moving point on the positive semi-axis of X axis, take AC as the right angle to make an isosceles right angle △ACD, ∠ ACD = 90, or even OD, and find the degree of ∠AOD;

(3) When the intersection point A intersects with E as the vertical line of the Y axis, F as a point on the negative semi-axis of the X axis, G as a point on the extension line of EF, EG as a right-angled side as an isosceles Rt△EGH, and intersection point A as the vertical line of the X axis intersects with EH at M point or even FM point, does the equation = 1 hold? If yes, please prove it; If not, explain why.