X2-x-2 factorization

X2-x-2 factorization

Did you learn cross multiplication? This is a direct cross multiplication!
x2-x-2
1 -2
1 1
(x-2)(x+1)
∴x2-x-2=(x-2)(x+1)

If the square x B 6-y of - A is the same as the 2Y of 5 + x B of 7a, then X-Y=

-The square x B 6-y of a is the same as 5 + x B 2Y of 7a
-A ^ (2x) B ^ (6-y) and 7a ^ (5 + x) B ^ (2Y) are the same kind of topic. Does that mean?
The exponents of the same letters of the same category are equal,
Then, {2x = 5 + X}
6-y=2y
The solution is x = 5, y = 2
x-y=5-2=3

Consider (x-2y) as a whole, and merge the following congeners: the square of 2 (x-2y) - the cubic of 7 (x-2y) + the cubic of 3 (2y-x) - (2y-x)
Power

Square of 2 (x-2y) - cubic of 7 (x-2y) + cubic of 3 (2y-x) - (2y-x)
=Square of 2 (x-2y) + square of 3 (x-2y) - cubic of 7 (x-2y) + cubic of (x-2y)
=Square of 5 (x-2y) - cubic of 6 (x-2y)

Don't lose the moon and stars because you miss the sun

If you cry because you miss the sun, you will also miss the stars in the sky

To completely neutralize a strong acid solution, 10 g KOH solution with 5.6% solute mass fraction is needed. If 10 g NaOH solution with 5.6% solute mass fraction is used, the pH a of the solution after reaction is greater than 7 B and less than 7 C, which is equal to 7 d
There should be analysis, analysis, analysis. The answer is useless

The mass of KOH and NaOH is 0.56 G
The relative molecular weight of KOH and NaOH is 56 and 40 respectively,
So there are more NaOH than KOH in the same mass, that is, more oh -,
After neutralization, there is residual Oh -, so pH > 7

5x (x-3) = (x-3) (x + 1) by factorization
Such as the title

5x(x-3)=（x-3）（x+1）
5x(x-3）-(x-3)(x+1)=0
(x-3)(5x-x-1)=0
(x-3)(4x-1)=0
x1=3,x2=1/4

On the 1:5000 scale map, a rectangular land is 5.5cm long and 4cm wide. How many square meters is the actual area of this rectangular land?

5 △ 15000 = 27500 (CM) = 275 (m) 4 △ 15000 = 20000 (CM) = 200 (m) 275 × 200 = 55000 (M2) a: the actual area of this rectangular land is 55000 square meters

Mathematician's story, must be about 20 words, 2

Hua Luogeng (1910-1982) was born in Jintan County on the Bank of Taihu Lake in Jiangsu Province. He was put in the basket by his father Hua Laoxiang for good luck when he was born. He "entered the basket to avoid evil, and was 100 years old with Geng", so he was named Luogeng. Hua Luogeng was fond of playing since childhood, and also liked to make fun of others, but he did not pass the exam

Divide the square of (1 / A + 1 / b) by (1 / A-1 / b)
Divide the square of (1 / A + 1 / b) by (1 / A-1 / b)

Is it wrong to write it, and the following is missing square (1 / A + 1 / b) & sup2; / (1 / A & sup2; - 1 / B & sup2;) = (1 / A + 1 / b) & sup2; / [(1 / A + 1 / b) (1 / A-1 / b)] = (1 / A + 1 / b) / (1 / A-1 / b) = (B + a) / (B-A) (1 / A + 1 / b) & sup2; / (1 / A & sup2; - 1 / B & sup2;) = (B + a) & sup2; / (B & sup2; - A & sup2;) = (

How to divide an equilateral triangle into 9 triangles of the same shape and size

Divide the three sides into three equal parts and make parallel lines of the third side through the equal points on both sides. Divide the equilateral triangle into nine triangles of the same size and shape