Equation: Xiaoli and Xiaoming are on the 400 meter circular track. Xiaoli runs 220 meters per minute and Xiaoming runs 280 meters per minute. They run in the opposite direction at the same point at the same time. How many minutes do they meet? It's an equation. Don't make a mistake

Equation: Xiaoli and Xiaoming are on the 400 meter circular track. Xiaoli runs 220 meters per minute and Xiaoming runs 280 meters per minute. They run in the opposite direction at the same point at the same time. How many minutes do they meet? It's an equation. Don't make a mistake

Let's meet in X minutes
220x+280x=400

Xiao Li and Xiao Ming practice running on the 2000 meter circular track. Xiao Li runs 220 meters per minute and Xiao Ming runs 280 meters per minute
(1) If two people run from the same starting point and in the same direction at the same time, Xiaoli falls down at the beginning of the run. When Xiaoli continues to run, it's just a minute late. How many minutes later, Xiaoming and Xiaoli meet for the first time?
(2) If two people run backward from the same starting point at the same time, can they be 800 meters apart after 6 minutes? If so, find out the time? If not, explain the reason

1) Xiao Ming is faster than Xiao Li = 280-220 = 60m. Xiao Ming and Xiao Li meet for the first time. Xiao Ming runs one more lap than Xiao Li, which makes X minutes x * 280 - (x-1) * 220 = 2000x = 89 / 3 minutes 2) (280 + 220) * 6 = 3000m, 3000-2000 = 1000m, 6min distance 1000m (2000-800) / (280 + 220) = 2.4min distance

On the 400 meter circular track, Zhang Qiang runs 320 meters per minute, and Li Na runs 280 meters per minute. Zhang Qiang and Li Na start from the same direction at the same time. When they meet for the first time in t minutes, it is t=______ ．

Let two people meet for the first time in t minutes. From the meaning of the question, 320x-280x = 400, the solution is: x = 10

How to simplify a = 1-1 / a into quadratic equation of one variable, and how to simplify a = 1-1 / A, and 1-1 / a = 1-1 / a

A = 1-1 / A, both sides multiply by a at the same time
Quadratic equation of one variable a & # 178; - A + 1 = 0
This equation has no real roots
An equation like a = 1-1 / A is called a fractional equation
His solution is to multiply both sides of the equation by the simplest common fraction of each term in the equation and transform it into an integral equation
Note that the solution of the fractional equation will produce an increasing root (such that the denominator equals zero root), so it must be tested