A classmate said: "Xiao Li and Xiao Fang are both 1.6 meters tall, but Xiao Fang insists that her height is 7 cm higher than Xiao Li. Is this possible? Why?

It's possible, because the height of Xiao Li and Xiao Fang is 1.6 meters, which is higher than that of Xiao Li. Xiao Li's height is 155 cm and Xiao Fang's height is 162 cm, which is 1.6 meters after rounding

Xiaojun and Xiaoming are 2.22 meters tall, Xiaoming and Xiaoli are 2.20 meters tall, Xiaojun and Xiaoli are 2.24 meters tall?

2.22+2.20+2.24=6.66
6.66/2=3.33
Xiaoli: 3.33-2.22
Xiaojun: 3.33-2.20
Xiao Ming: 3.33-2.24
Can you see clearly in this way?

Xiao Ming and Xiao Li are walking on the 400 meter track. If they are walking in opposite directions at the same time, they will meet in 4 minutes. If they are walking in opposite directions at the same time, Xiao Ming will catch up with Xiao Li for the first time. How many meters do Xiao Ming and Xiao Li walk each minute?
Xiao Li walks x meters per minute, Xiao Ming walks (400-4x) / 4 meters per minute, that is, (100-x) meters, 20 (100-x) - 20x = 400, x = 40, 100-x = 60. A: Xiao Ming and Xiao Li walk 60 and 40 meters each minute
I don't understand why it is equal to 400, Xiao Li's journey is reduced, and Xiao Ming's journey is equal to 400?
20 (100-x) - 20x = 400 Xiaoming's journey Xiaoli's journey = 400, very strange, why?

Reverse is the problem of meeting, two people walk a circle of 400 meters
Walking in the same direction is a matter of catching up. Xiao Ming walks 400 meters more than Xiao Li

Using Karnaugh map to simplify logic function y = f (a, B, C, d) = ∑ m (3,4,5,7,9,13,14,15),

Using Karnaugh map to simplify the logic function y = f (a, B, C, d) = ∑ m (3,4,5,7,9,13,14,15), analysis: because Karnaugh map is not easy to draw, the description is as follows: 1. Mark the given minimum term in Karnaugh Map: m3, M4, M5, M7, M9, M13, M14, m152, cycle minimum term (M3, M7), (M4, M5), (M9, M13), (M14, M15) 3

Using Karnaugh map to simplify logic function: F = ∑ m (1,3,8,9,10,11,14,15)

Let's assume that ABCD, after simplification according to Karnaugh map, we get
F = AB non + B non D + AC

In logic function, Karnaugh map reduces f (a, B, C, d) = ∑ (2,3,6,7,8,10,12,14)

A 'C + ad' ('for non)

Using Karnaugh map method to simplify function f (a, B, C, d) = ∑ m (0,2,5,6,7,9,10,14,15)

F=BC+CD'+A'B'D'+A'BD+AB'C'D

How to reduce the 1 / 2 power of (X-P) = x to the square of X - x + P = 0

（x-p)^1/2=x
Square of two sides: X-P = x ^ 2
Transfer: x ^ 2-x-p = 0

How to simplify the general form of quadratic equation with one variable x * 1 = (1-x) ^ 2

X * 1 = (1-x) ^ 2 Expansion:
X = 1-2x + x ^ 2 shift:
x^2-3x+1=0

How to simplify a cubic equation of one variable to a quadratic equation of one variable

One variable cubic is an unknown number to the third power. You can eliminate the unknown first. For example, x3-4x = 0 is to propose an X, and the result is x (x2-4) = 0, and the result is x = 0 or x = +? U 2
You have to give examples to work out your topic!

A classmate said: "Xiao Li and Xiao Fang are both 1.6 meters tall, but Xiao Fang insists that her height is 7 cm higher than Xiao Li. Is this possible? Why?