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Because ad bc,ea ad, mbe=45° mbe is an isosceles right triangle, so be = me and because bae= mce, aeb = mec = 90° so abe mce
So ab=cm ( is right).
As you can see from the diagram, the MCE is rotated 90° counterclockwise to coincide with ABE.
i.e. MC and AB at 90° (right).
Because BMC = 180°- mbe - mce = 135°- mce
The title doesn't say what degrees MCE is equal to, so it's not certain that BMC=90° (which is wrong).
Because f and g are the midpoints of ab and cm, respectively.
In a right triangle, the midline length of the hypotenuse is equal to half of the hypotenuse.
i.e. 2ef = ab; 2eg = cm
And because of the abe MCE
So ef = cm ( is right).
Because fb = ef = eg = gm
be = me
So bef emg
So fbe = meg
The same can be seen. aef ≌△ecg
i.e. MEF = MCE
So feg = meg + mef
fbe + mce
fbe + bae
So EFG is an isosceles right triangle ( is correct).
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Correct serial numbers 1, 2, 4
Analysis: ABE AEC from AEC= AEB=90°, BAE=MCE, AE=AE
So ab=cm 1 is correct.
Since f g is the midpoint of the hypotenuse of the right triangle, there is ef=(1 2) ab and eg=(1 2) cm
So ef=eg 2 is correct.
Extend the CM line to cross AB to K
Since ecm= bae, bae+ abe=90°,,fem<45, so ecm+ kbc=90°, so ckb=90°
So ab cm 4 is correct.
Since mbe=45°, bme=90°-45°=45°, abe >45°, cme= abe>45°, bmc= bme+ abe >(45+45=90) 90° 3 is wrong.
feb =∠abe>45,,∠fem<45
fg bc,, emf= emg=90, efm emg,fem<45°,= meg<45,°,feg<90° 5 error.
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Because. ad bc,ea ad, mbe=45° so mbe is an isosceles right triangle, so. beme again because. bae=∠mce,∠aebmec
So. abe≌△mce
So ab=cm
That's right) as can be seen in the diagram.
A 90° counterclockwise rotation of the MCE coincides with the ABE.
Namely. MC and AB at 90°
That's right) because of BMC
mbemce
MCE is not mentioned in the MCE title
Equal to how many degrees, so.
Not sure. bmc=90°
is wrong) because f and g are the midpoints of ab and cm, respectively.
In a right triangle, the midline length of the hypotenuse is equal to half of the hypotenuse. Namely. 2efab;2eg
cm again.
Abe MCE So. ef
cm is right).
Because fb = ef = eg = gm
beme, so bef
emg, so fbe
The same can be said for meg.
aef△ecg
i.e. MEF = MCE
So. feg
megmef
fbemce
fbebae
So EFG is an isosceles right triangle.
That's right)
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Let the bread sold be x, the remaining bread be y, and the remaining biscuits be 2yx+y+2y=8+9+16+20+22+27=102x+3y=102
According to the option, y is known to be an integer.
3y=102-x
102-x must be divisible by 3.
102 is divisible by 3.
then x should also be divisible by 3.
x=9 or 27
Let x=9 y=52
orx=27 y=40
Check x=9y=52=8+22+9+16
Y=40 cannot be composed of the above integers.
So the answer is d
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Eliminate z and you're good to go. That is, Lianli.
x + y +4z = 1 and x = y + z
From x +y +4z=1 we get 4z=1-x 2-y 2 so x =y +z gives 16z 2 =16x 2 -16y 2 so the squares of both sides are brought in : get (1-x 2-y 2 ) 2 =16x 2 -16y 2
It can be simplified to get x 4 +y 4 +1-18x 2 +14y 2 +2x 2 y 2=0
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The cylindrical equation is: 5x 2 - 3y 2 = 1
Parse: x2 + y2 + 4z2 = 1 .Equation 1).
x^2 = y^2 + z^2 ..Equation 2).
Because the busbar is parallel to the z-axis, there is no z in the cylindrical equation, that is:
We're going to use (Equation 1) and (Equation 2) to get rid of z.
According to (Eq. 2), z 2 = x 2 - y 2
Substituting (Eq. 1) yields: x 2 + y 2 + 4 (x 2 - y 2) = 1
To simplify: 5x 2 - 3y 2 = 1
Actually, this equation is not a cylinder, but a shape similar to a vertical hyperboloid, as shown in the figure below
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It should be known that the distance from the point to the straight line is 1, so use the formula in the figure.
d=丨3 2+4 1-4b丨 (3 +4 )=1, then 丨10-4b丨=5
Go to the absolute value symbol, you can get.
10-4b = 5, when 10-4b = 5, b = (10-5) 4 = 5 4, when 10-4b = -5, b = (10 + 5) 4 = 15 4.
In summary, the b-value is 5 4 or 15 4.
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The first step is the distance formula, which substitutes the xy value of the coordinates.
The second step is the absolute value of 10-4b = 5, so 10-4b = 10-5 or 10+5, you can solve it.
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The distance that Zhang Qiang continued to walk was the distance that Wang Ping had walked before. =10* = 15km。
Total length = 15 (7 12) = 180 7 Zhang Qiang's previous distance = 180 7 - 15 = 75 7 Zhang Qiang's walking time = 75 7 10 =75 70 = Wang Ping's walking time s=l t=15 (75 70)= 14km h
Solution: From y=mx 2+3mx-4m, it can be known:
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f(x)=(ax+b) (x +1), in (- is the odd function.
f(-x)=-f(x)..or f(0)=0=>b=0]>(ax+b) (x +1)=-(ax+b) (x +1)>(ax+b)=-(ax+b). >>>More
7.Solution: 32g-26g=6g
Set the volume to xcm3 >>>More
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Solution: Suppose the second count is x times. >>>More