Make up an application problem of solving the system of linear equations of two variables, so that the solution of the system of equations is 9,10

Make up an application problem of solving the system of linear equations of two variables, so that the solution of the system of equations is 9,10

Let x participate and y not participate
1、x=3y
2. The total number of students is x + 3Y, less than 6 is x + 3y-6, and the number of students who do not participate plus 6 is y + 6, so the number of students who participate is x + 3y-6-y-6 = x + 2y-12
The ratio of participants to non participants is 2:1, that is, (x + 2y-12) / (y + 6) = 2
2, the solution is: x = 24, y = 8, the total number of people is 24 + 24 = 48

Mathematical problems of ternary linear equations
x+2y+2z=3
3x+y-2z=7
2x+3y-2z=10
x-y=2
z-x=3
y+z=-1
x-y-z=2
3x+5y+7z=24
4x-y-2z=26
In AX2 + BX + C, when x is 1,2,0 respectively, the values of AX2 + BX + C are 3, - 1,2 respectively
Wait a minute! Be complete
Good + points~

1.x=1,y=2,z=-1
2.x=-1,y=-3,z=2
3.a=-5/2,b=7/2,c=2
I won't say anything else. Take your time~

The derivative of the function y = - x3-x at (4,1) is

y'=-3x^2-1=-3*4^2-1=-49

When the numerator of a fraction is three times larger and the denominator is three times smaller, it will be two and one seventh. What is the original fraction?

2 / 7 1 / 9 = 15 / 7 / 9 = 5 / 21
The original score was 5 / 21

The general solution of the differential equation: Y "- 6y '+ 13y = 0 is as follows:

The characteristic equation is R ^ 2-6r + 13 = 0
r=3±2i
So the general solution is y = e ^ (3x) (c1cos2x + c2sin2x)

Find the rules and fill in the blanks, 1 10 3 8 5 6 ()

7
1, 3, 5, 7; 10, 8, 6

The same Chinese character stands for the same number, and different Chinese characters stand for different numbers
Mathematical riddle multiplied by 9

1089
* 9
--------
nine thousand eight hundred and one

Given that a, B, C and D are four points in space, and a, B, C and D are not coplanar, then the positional relationship between AB and CD is______ ．

∵ a, B, C and D are the four points in space, and a, B, C and D are not coplanar. If the lines AB and CD intersect, then a, B, C and D are coplanar, but the lines AB and CD cannot intersect. If the lines AB and CD are parallel, then a, B, C and D are coplanar, and the lines AB and CD cannot be parallel

If the intersection of the right branch of the hyperbola and the straight line is not coincident, the value range of the real number k is obtained

As shown in the figure, the straight line y = kx-1 passes through P (0, - 1). By rotating the straight line L passing through P around P, it can be seen that when k increases from 1, it begins to have two intersections with the right branch of the hyperbola [∵ the asymptote is y = ± X & nbsp; & nbsp; k = ± 1], K increases, and the two intersections slowly approach
X & # 178; - (kx-1) &# 178; = 1 & nbsp; & nbsp; & nbsp;, that is, (1-k & # 178;) x & # 178; + 2kx-2 = 0 has multiple roots, 4K & # 178; + 8 (1-k & # 178;) = 0. & nbsp; & nbsp; k = √ 2 & nbsp; & nbsp; [- √ 2 in the left branch. Delete]
When 1 ﹤ K ﹤ 2, the intersection of right branch of straight line and hyperbola does not coincide

How to add operation symbol in 123456 to be equal to 75

(1*2+3+4+6)*5=75