180°-x°=0.5x°

180°-x°=0.5x°

By shifting items and merging similar items, 1.5x ° = 180 ° is obtained
Divide both sides by 1.5 at the same time, there is: X ° = 120 °
Then x = 120
Among the following equations, the one suitable for factorization is
A.2x^+x-2=0
B.2x^-4x-5=0
C.4x^-4x+1=x^
D.x^+3x+7=0
Choose C
4x^2-4x+1=x^2
（2X-1)^2-x^2=0
(2x-1-x)(2x-1+x)=0
(x-1)(3x-1)=0
C. It can be (2x-1) ^ 2 = x ^ 2
Use factorization to solve the following equation
（2x-3)^=9(2x+3)^
Note: ^ is square >
（2x-3)²=9(2x+3)²
（2x-3)²-9(2x+3)²
=（2x-3)²-(6x+9)²
=(2x-3-6x-9)(2x-3+6x+9)
=-(4x+12)(8x+6)=0
Get x = - 3 or x = - 3 / 4
(2x-3)^=9(2x+3)^ = (3(2x+3))^ = (6x+9)^
2x-3 = soil (6x + 9)
（1）
2x-3 = 6x+9 x = 1.5
（2）
2x-3 = -6x-9 x = -0.75
Simplify (A & sup2; - 2Ab) - (3a & sup2; + 3AB) = ()
Decomposition factor AB-A + B-1 = ()
Factorization 2xy-x & sup2; - Y & sup2; + 1
（a²-2ab)-(3a²+3ab)
=a²-2ab-3a²-3ab
=-2a²-5ab
=-a(2a+5b)
ab-a+b-1
=a(b-1)+(b-1)
=(a+1)(b-1)
2xy-x²-y²+1
=-(x²-2xy+y²)+1
=-(x-y)²+1
=-[(x-y)²-1]
=-(x-y+1)(x-y-1)
（a²-2ab)-(3a²+3ab)=a²-3a²-2ab-3ab=-2a²-5ab=-a(2a=5b)
ab-a+b-1=a(b-1)+(b-1)=(a+1)(b-1)
2xy-x²-y²+1=1-(x+y)^2=(1-x-y)(1+x+y)
1. The original formula = A & sup2; - 2ab-3a & sup2; - 3AB
=-2a²-5ab
=-a(2a+5b)
2. Original formula = (AB-A) + (B-1)
=a(b-1)+(b-1)
=(b-1)(a+1)
3 the original formula = 1 - (X & sup2; - 2XY + Y & sup2;)
=1²-(x-y)²
=(1+x+y)(1-x+y)
Why is the limit of limx approaching 0 3x / X & # infinite
Lim3x / xsquare = lim3 / X
Because x approaches zero, then lim3 / x = infinity
A store is going to sell a certain kind of clothing at a discount because of the season change. If each clothing is sold at a 50% discount on the price, it will lose 20 yuan, and if it is sold at a 20% discount on the price, it will earn 40 yuan? (2) What is the cost of each garment? (3) How much discount can I get at most to ensure no loss?
(1) Suppose that the price of each garment is x yuan. According to the meaning of the question, we get 0.5x + 20 = 0.8x-40, and the solution is x = 200. Answer: the price of each garment is 200 yuan. (2) according to the meaning of the question, we get 200 × 0.5 + 20 = 120 yuan. Answer: the cost of each garment is 120 yuan. (3) if you set a discount of Y, you will not lose money
The key of factorization by extracting the common factor is to determine the common factor, and the coefficient of the common factor is the ratio of each coefficient------------------
The key of factorization by extracting common factor is to determine the common factor. The coefficient of the common factor is the largest common divisor of each coefficient-----------
Limx tends to infinity x-178; - 1 / 2x-178; - X-1 to find the limit
Limx tends to infinity X & # 178; - 1 / 2x & # 178; - X-1 = 1 / 2 catch the big head or divide by x ^ 2
Mathematical problem, 1 yuan quadratic equation application problem - average growth rate problem. Please help to solve it
The vegetable production of a village in 2005 increased by 44% compared with that in 2003
Solution 1: suppose: the average annual growth x is: (1 + x) ^ 2 = 1 + 44% (1 + x) ^ 2 = 144% 1 + x = ± 6 / 5x = (± 6 / 5) - 1, so X1 = 1 / 5, X2 = - 11 / 5 (rounding off) 1 / 5 = 20%, so the average annual growth is 20%. Solution 2: suppose: the average annual growth x, the total output value in 2003 is a (a ≠ 0, because a is the total output value
(1+x)^2=1.44
1+x=1.2
x=0.2
20%
Suppose the average growth rate is x and the output in 2003 is 1, then
1*(1+x)*(1+x)=1*(1+44%)
Get x = 20%
So the average annual growth rate is 20%
Suppose the average growth rate is x and the output in 2003 is 1, then
1*(1+x)*(1+x)=1*(1+44%)
Get x = 20%
So the average annual growth rate is 20%
Extract common factor / factorization
How to reduce x ^ 2 * Z ^ 3 + x ^ 3 * y ^ 2 + y ^ 3 * Z ^ 2-x ^ 3 * Z ^ 2-x ^ 2 * y ^ 3-y ^ 2 * Z ^ 3 to the product of four factors?
(X - Y) (X - Z) (Y - Z) (X Y + X Z + Y Z)
Method: first observe that when x = y = Z, the formula is 0, and because the formula is symmetric, it must contain the first three factors. Extract the first three factors and find the last one~