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People's education press, item 2 on page 5 of compulsory English for senior one
Answerkey for Exercise 2:1 Anne said that she did not know theaddress of her new home.2 Anne told her father that she had gottired of looking at nature through dirty curtains and dusty windows.3 The g...
People's education press senior high school English compulsory 3 all long article translation each unit must
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If a farmer harvests wheat x HA / h, then a harvester harvests 150x HA / h
Ten
100x＝10
150x+1，
The solution is: x = 1
30，
After testing, x = 1
30 is the root of the original equation
The harvester harvests wheat every hour: 1
30 × 150 = 5 ha,
A: This harvester harvests 5 hectares of wheat per hour
People's education press, eighth grade mathematics, Volume 2, page 24
16. (1) fraction of a (the third power of a plus 4V)
（2） Part of BC (Part B, Part C, part 2BV, part 2CV)
(3) [2 (B plus C minus 2a) v]
As shown in the figure, in △ ABC, ∠ ACB = 90 °, CD ⊥ AB is at point D, point E is on AC, CE = BC, perpendicular line of AC is made through point E, and extension line of intersection CD is at point F Confirmation: ab = FC
It is proved that: ∵ Fe ⊥ AC at point E, ∵ ACB = 90 °,
∴∠FEC=∠ACB=90°．
∴∠F+∠ECF=90°．
And ∵ CD ⊥ AB at point D,
∴∠A+∠ECF=90°．
∴∠A=∠F．
In △ ABC and △ FCE,
∠A＝∠F
∠ACB＝∠FEC
BC＝CE ，
∴△ABC≌△FCE（AAS），
∴AB=FC．
When a B is a value, the sum of a / x + 2 and B / X-2 is 4x / x? - 4? When a is the value of a, the solution of the equation x + A / a (x-1) = - 4 / 5 is x = - 1 / 5? Mr. Li gave a question in class: if the solution of the equation A / x + 1 = 1 about X is negative, find the range of A Remove the denominator and get a = x + 1 ∴x=a-1 ∵ the solution of the equation is negative ﹤ A-1 ﹤ 0 leads to a ﹤ 1 When a < 1, the solution of equation A / x + 1 = 1 is negative Is his solution wrong? If there is any error, please explain the reason for the error and write the correct solution; if there is no error, please explain the basis of each step
1./x+2+b/x-2=4x/x²-4
That is a (X-2) / x? - 4 + B (x + 2) / x? - 4 = 4x / x? - 4
X + 2 and X-2 are not 0
Then ax-2a + BX + 2B = 4x
That is, a + B = 4, - 2A + 2B = 0
So we get a = b = 2
2. Bring in x = - 0.5 and a = 5
Obviously, the above process is wrong
Supplement a is not equal to 0
Given that the line segment AB = 4, point C is a point in the plane (not coincident with a and b), m and N are the midpoint of line Ca and CB respectively (1) When C is on the segment AB, as shown in the figure, find the length of Mn; (1) When C is on the extension line of line AB, draw the figure and calculate the length of Mn; (2) When C is outside the straight segment AB, draw a figure, measure it, and write the length of Mn (do not write the reason)
(1) ∵ m and N are the midpoint of Ca and CB respectively,
∴CM=1
2AC，CN=1
2BC，
And ∵ AB = 4,
∴MN=1
2（AC+BC）=1
2AB=2．
(2) As shown in the figure:
The midpoint of Ca and CB are,
∴CM=1
2AC，BN=1
2BC，
And ∵ AB = 4,
∴MN=CM-CN=1
2（AC-BC）=1
2AB=2．
（3）
Mn = 2
Cattle grazing problem: If there is a pasture that grows evenly every week and can feed 20 cows for 10 weeks or 24 cows for six weeks, how many weeks can this pasture feed 18 cows? If 12 people can scoop water for 3 hours, for example, 8 people can scoop water in 5 hours. If it is required to finish bailing in 2 hours, how many people should be arranged to scoop water? There is a jar of wine, which leaks the same amount of wine every day. If 12 people drink this jar of wine, it will be finished in 4 days; if 9 people will drink it, it will be finished in 5 days. What percentage of the original wine will be drained every day? Cattle grazing problem: How many pieces of pasture can feed cattle for 20 weeks? A ship finds that some water has been put into the water, and the water at the leak is entering the ship at a uniform speed. If 12 people can spoon water for 3 hours, for example, 8 people can spoon water for 5 hours. If 2 hours is required, how many people should be arranged to spoon water? There is a jar of wine, which leaks the same amount of wine every day. If 12 people drink this jar of wine, it will be finished in 4 days; if 9 people will drink it, it will be finished in 5 days. What percentage of the original wine will be drained every day?
1. Suppose that cattle eat grass every week as X, forage grows every week, and the number of original forage is a, then the equations can be formulated, 10 * 20x + A + 10Y = 0, 24 * 6x + A + 6y = 0 (one is to eat, the other is to grow, and the last is to get 0)
First question: 1? + 2? + 3? + ·· + 15? = 14 400, and calculate the value of 2? + 4? + 6? + ·· + 30 The second question: Observe the following 1³=1² 1³+2³=3² 1³+2³+3³=6² 1³+2³+3³+4³=10² Guess the result of 1 3 + 2 3 + 3 3 + ·· + 10 3 Third question: calculation: 99 999×22 222+33 333×33 334
1. If 2,4,6 are transformed into 2 * 1,2 * 2,2 * 3... The cube of 2 is multiplied by (1's cube + 2's cube + 3's Cube...) i.e. 8 * form = 1152002. According to the first two formulas, it can be concluded that the number on the right of the equation is the sum of the numbers on the left, that is, the cube of 1 + the cube of 2 +... + the cube of 10 = (1 + 2 + 3 + 4 + 5
Calculation: (X-Y + 2) (x + y + 2), (3x-2y-1) (3x + 2Y + 1y-2y-1y-4y-4y ^ 2.calculation: (X-Y + 2) (x + y + 2), (3x-2y-1) (3x + 2Y + 1), (4x + 2Y + 1), - 4x ^ 3Y * [7x ^ 2y-3x + (2XY) (2XY) ^ 3]. Simplify and then evaluate: X (2x + 1) (1-2x) - 4x-4x-2x) - 4x (2x + 1) (1-2x) - 4x) - 4x (2x) - 4x-2x + 1) (1-2x) - 4x-2x-2x-2x-2x-2x-2x-2x-2x-2x if m ^ 2-2m + n ^ 2 + 4N = - 5, then M + n =?, Given that the solution of the system of equations 3x + 2Y = m + 2,2x + 3Y = m is suitable for x + y = 8, then M =,
a^3-a=a(a^2-1)=a(a-1)(a+1)b^2（x-3)+b^2（3-x)=b^2(x-3)-b^2(x-3)=016(m-n)^2-9(m+n)^2=[4(m-n)-3(m+n)][4m-4n+3m+3n]=(4m-4n-3m-3n)(7m-n)=(m-7n)(7m-n)4x^2(x-y)+(y-x)=4x^2(x-y)-(x-y)=(4x^2-1)(x-y)=(2x-1)(2x...
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