Help to solve the quadratic equation - 6x + 3Y = 5 - 4x + 2Y = 8

Help to solve the quadratic equation - 6x + 3Y = 5 - 4x + 2Y = 8

-6x+3y=5①
-4X + 2Y = 8, then - 2x + y = 4
① - 2 × 3, then 0 = - 7
So the original equations have no solution

Solving the quadratic equation 2x = 2Y, 3Y + 4x = 33

From the first equation
x=y
The second equation is as follows
3x+4x=33
The solution is x = 33 / 7
y=33/7

Find the maximum value of the function y = Log1 / 3 ^ (x ^ 2-6x + 10) in the interval [1,2]? Please... Urgent... Now

This is a composite function; the main function Log1 / 3 G (x) (the base of the logarithmic function of the main function Log1 / 3 is a decreasing function)
True number G (x) = x ^ 2-6x + 10 (according to △ 0, according to image)
(- infinity, 3) g (x) is a decreasing function;
So in [1,2]; G (x) is a decreasing function
For compound function (same increase different decrease)
In [1,2]
y=log1/3^(x^2-6x+10)
It is an increasing function;
Ymax=y（2）=log1/3（2）

There are 20 male employees, 16 female employees and 12 over 30 years old in a company. What percentage of male employees are female employees?

20÷16=1.25=125%

Factorization of XY & #178; - x

xy²-x
=x（y²-1）
=x（y-1）（y+1）

There are 25 boys in class 6 (1), 3 more than 5 / 2 of the class. How many are there in the class?

(25-3) / 0.4 = 55 persons
Three more than 2 / 5 of the class, that is, 2 / 5 of the class is 22

Let X and y satisfy x2 + 2xy-1 = 0, then the value range of X + y is______ ．

∵ x2 + 2xy-1 = 0 ∪ (x + y) 2 = 1 + Y2 ≥ 1, then x + y ≥ 1 or x + y ≤ - 1, so the value range of X + y is (- ∞, - 1] ∪ [1, + ∞), so the answer is: (- ∞, - 1] ∪ [1, + ∞)

There are 260 trees planted by sixth graders and how many trees are planted by fifth graders?

260 × 1 / 5 + 12 = 52 + 12 = 64 trees

Given that the A-1 power of the equation x + 3 = a-5 is a unary linear equation of X, then a =?

The equation x to the power of A-1 + 3 = a-5 is a one variable linear equation about X, that is, the highest power of X is 1
So A-1 = 1
a=2

The sum of number a, B and C is 72. The number a is twice that of number B, and the number C is three times that of number B. what are the numbers a, B and C?

72/6=12
A = 24, B = 12, C = 36