As shown in the figure, if the line y = KX + B passes through two points a (3,1) and B (6,0), then the solution set of the inequality system 0 < KX + B < 13X is______ ．

As shown in the figure, if the line y = KX + B passes through two points a (3,1) and B (6,0), then the solution set of the inequality system 0 < KX + B < 13X is______ ．

Substituting a (3,1) and B (6,0) into y = KX + B respectively, 3K + B = 16K + B = 0, the solution is k = - 13b = 2, then the analytic expression of the function is y = - 13X + 2. The inequality group − 13X + 2 ＞ 0 − 13X + 2 ＜ 13X, the solution is 3 ＜ x ＜ 6. So the answer is 3 ＜ x ＜ 6

Given the solution of equation 3-4 (x + 1) = 0, the solution of equation x + k-2k = 3x is reciprocal to each other, and the value of K is obtained

Let 3-4 (x + 1) = 0 be equation 1
(x + k) / 3-2k = 3x is equation 2;
The solution is: where x = - 1 / 4
Because: the solutions of 1 and 2 are not opposite
So: in formula 2, x = - 4;
By substituting (x + k) / 3-2k = 3x in formula (2), we can get the following result:
（-4+k）/3-2k= -12
k=-32/7

It is known that the solution of the linear equation KX + x = 2 + 1 (k is not equal to - 1) with respect to X is also an integer when k is an integer value

kx+x=2+1
x=3/(k+1)
k=-4,-2,0,2

What is the difference between marble and granite?
The application in the interior and exterior decoration of buildings

The main content of stone is quartz mesh mullite, fine stone, high density, 2.71g/cm3, that is, the main defense King 2710 kg / m3, strong wood in the construction of soil you king degree of hardness, with natural grain (after rough grinding is particularly prominent), after a series of physical and other main network of the main academic experiments, the unit strength compression is 165mp

Given that u = {1,2,3,4,5,}, a = {x | x ^ 2-5x + q = 0, X belongs to u}, then the value of Q is () a.0,2,4 b.1,4,6 c.4,6 d.0,16
None of the options I calculated were right

First of all, let x ^ 2-5x + q = 0, and the root of x ^ 2-5x + q = 0 be x 1, x 2; then x 1 + x 2 = 5, and because x 1, x 2 belong to u, there are only two cases,
1,x1=2,x2=3；
2,x1=1,x2=4；
So q = X1 * x2 = 4 or 6

A cylinder has a bottom radius of 3 cm and a height of 20 cm. What is the surface area of the cylinder in square centimeters? What is its volume in cubic centimeters?

Surface area: 3.14 × 3 square × 2 + 2 × 3.14 × 3 × 20
=3.14×9×2+6.28×3×20
=28.26×2+18.84×20
=56.52+376.8
=433.32 (cm2)
Volume: 3.14 × 3 square × 20
=3.14×9×20
=28.26×20
=565.2 (cm3)

The ratio of a number to 5 / 9 is equal to 3 / 4 of 20,

Let this number be X
Then x / (9 / 5) = 20 × 3 / 4, x = 15 × (9 / 5) and x = 27

The equation of line L is x-y-2 = 0, and its symmetric linear equation about point (1,4) is?

Let 2 points (2,0) on the line; (0, - 2) be symmetric with respect to point (1,4)
We get (0,8); (2,10)
The line passing through these two points is the symmetrical line X-Y + 8 = 0

If you add a percent sign to a number, it will be reduced by 19.8, which was ()

Let this number be X
X/100=X-19.8
X=100(X-19.8)
99X=1980
X=20
You can check it, OK,!

*What operation symbol in mathematics

In the general machine or electronic system, it represents the multiplication sign, but in the field of mathematics, it is meaningful and represents the operation method specified by a certain person, which is very common in later learning