System of inequalities In a visit activity, students are divided into eight groups. If each group is more than one person, the number of visitors is more than 156. If each group is less than one person, the number of visitors is not more than 150.

Each group has 19 people
Suppose there are x people in each group
That is (x + 1) 8 > 156
（x-1）8

There are 48 students in a class. Everyone can play chess or go. The number of people who can play chess is 3 times less than that of people who can play go. The number of people who can play both kinds of chess is at most 9, but not less than 5. How many people can play go?
Solutions to a series of inequalities

There are x players who can play go, 2x-3 players who can play chess
x+2x-3-49≤9
x+2x-3-49≥5
==>19≤x≤61/3
==>19 ≤ XX = 19 or x = 20

Mathematical problems on inequality system
Inequality system X-Y + 2 > = 0 x + y + 2 > = 0 2x-y-2

y=x+2,
y=X-2,
y=2x-2,
The distances from the center O (0.0) to the three straight lines are (calculated by the formula of the distance from point to line): √ 2 (root 2), √ 2,2 / √ 5 (minimum),
So the radius of the circle R ≤ 2 / √ 5
So the maximum area of the garden is: π. R square = 4 π / 5
It's more convenient to draw a picture by yourself,

Solving the system of inequalities: − 12x ≥ 211 − x > 1 − 3x

To solve the first inequality, we get - x ≥ 4 by removing the denominator, X ≤ - 4 by solving the second inequality, 2x ＞ - 10 by combining the similar terms, and X ＞ - 5 by solving the second inequality. The solution set of the inequality system is - 5 ＜ x ≤ - 4

System of inequalities In a visit activity, students are divided into eight groups. If each group is more than one person, the number of visitors is more than 156. If each group is less than one person, the number of visitors is not more than 150.