The positive integer solution of inequality 2x + 9 ≥ 3 (x + 2) is______ ．

The positive integer solution of inequality 2x + 9 ≥ 3 (x + 2) is______ ．

2X + 9 ≥ 3 (x + 2), remove bracket, 2x + 9 ≥ 3x + 6, shift term, 2x-3x ≥ 6-9, merge similar term, - x ≥ - 3, coefficient is 1, X ≤ 3, so its positive integer solution is 1, 2, 3. So the answer is: 1, 2, 3

Inequality 2x + 1 + 1 / x-3

According to the meaning of the title, X ≠ 3
Reduced to: 2x

The solution set of inequality 2x + 3 > 9 is______ ．

If we divide the two sides by two, we get x > 3

Given that x = 3 is the solution of the equation 2 / x-a = X-1, then the inequality (5-a) x

Substituting x = 3 into the equation (x-a) / 2-2 = X-1, the solution is a = - 5
Then the inequality (5-a) x < 1 / 2 can be reduced to 10x

How to calculate the relative density of sand and gravel?

It seems that there is no specific calculation formula. You can find the material manual. There may be an empirical formula. Either use the drainage method or divide the used mass by the volume of gravel

－7+13－6+20= （－49）－（+91）－（-5）+（-9）= 1+（-2）+|－2－3|－5= （-5）x（-7）－5x（－6）=

－7+13－6+20
=（-7-6）+13+20
=20
（－49）－（+91）－（-5）+（-9）
=-49-91+5-9
=（-91-9）+（5-49）
=-100-44
=-144
1+（-2）+|－2－3|－5=
=1-2+5-5
=-1
（-5）x（-7）－5x（－6）
=35+30
=65

Three 5-decimeter-long columns with the same bottom area are put together to form a large column, and the surface area is reduced by 12.56 square decimeters. What is the volume of the large column?

12.56 △ 4 × (5 × 3), = 3.14 × 15, = 47.1 (cubic decimeter), a: the volume of the large cylinder is 47.1 cubic decimeter

Eight consecutive numbers 1.2.3.4.5.6.7.8 are divided into two groups. The first group is divided into three numbers, and the second group is divided into five numbers

Let the sum of eight numbers be 36. Let the sum of three numbers in the first group be X. from the meaning of the question, we can get: 2x = 36-x, we can get x = 12. From x = 12, we can see that the three sets of numbers in the first group are: (1,3,8), (1,4,7), (1,5,6), (2,3,7), (2,4,6), (3,4,5), and the corresponding sets of five numbers in the second group are obtained

When y is an odd function and X is less than zero, the square of y = x + 3x + 2x belongs to the closed interval 1-3, and the minimum value of Y is?
The whole calculation process
X is less than 0, y = x ^ 2 + 3x + 2
X is greater than 0, y = x ^ 2-3x + 2
=(x-3/2)^2-1/4
Axis of symmetry x = 3 / 2
If the minimum value x = 3 / 2 is obtained, then y = - 1 / 4, is this algorithm wrong?

Let x > 0, then when - x0,
F (x) = - f (- x) = - x ^ 2 + 3x-2,
When x is a closed interval [1,3], the minimum value is f (3) = - 2

5 / 6 of a number is 4 more than 3 / 4 of it. Find the number

4÷（5/6-3/4）=48