Solve the equation 20-5x = 8x-6 I have a headache My sister's math problem. I don't know my education

Solve the equation 20-5x = 8x-6 I have a headache My sister's math problem. I don't know my education

transposition
20+6=8x+5x
26=13x
x=26÷13
x=2

5x-8 = 8x + 1 (solving equation)

5x-8=8x+1
8x-5x=-8-1
3x=-9
x=-3
Do not understand welcome to ask

Solving equation (1 / 2x-1) (1 / 2x + 1) + 1 / 4 = 1 / 2x needs process and answer

（1/2x-1）（1/2x+1）+1/4=1/2x
1/4x²-1+1/4=1/2x
x²-4+1=2x
x²-2x-3=0
(x+1)(x-3)=0
x1=-1,x2=3

Fill in with prime numbers: () + () + () = 71 () + () + () = 81 () &# 10006; &# 65039; () &# 10006; &# 65039; () = 8
（）+（）=（）+（）=（）+（）=40

（3）+（7）+（61）=71
（7）+（13）+（61）=81
（2）✖️（2）✖️（2）=8
（3）+（37）=（11）+（29）=（17）+（23）=40

Let the probability density of two-dimensional random variables (x, y) be f (x, y) = 6x, & nbsp; 0 ≤ x ≤ y ≤ 10, & nbsp; & nbsp; other, then p {x + y ≤ 1}=______ ．

As shown in the right figure: the probability is transformed into integral over area D, which is set by the question: P {x + y ≤ 1} = ∬ DF (x, y) DXDY ∫ 120 (6x − 12x2) DX = 14, so the answer is: 14

If the symmetry axis of quadratic function f (x) is x = - 1, the minimum value is - 4, and the length of its image cut on the X axis is 4, find f (x)

f（x）=（x-1)(x+3)
If the symmetry axis is - 1 and the intercept of the X axis is 4, then the left and right sides of - 1 have two units respectively. If they intersect with the X axis, then the intersection points are - 3 and 1 respectively
We get f (x)

Greatest common factor of 12 and 18 and 42

6

If a and B are rational numbers, a new operation "*": a * b = 1 / 5 times [3a-2b], [1 * 9] * [9 * 6] is defined
No explanation

It's one-fifth times 3a-2b
It's 3a-2b out of 5

For the known line segments a and B (a > b), draw a line segment so that it is equal to:
（1）a+3b；
answer
（2）1/2（a-b）.
answer
How to draw

1. For ray AP, take a as the end point, intercept AB = a, take B as the end point, intercept BC = B on ray BP, then take C as the end point, intercept CD = a on ray CP, and then take D as the end point, intercept de = B on ray DP, then line AE = a + 3b is the line segment; 2. Make line ah = a, take a point P on line ah to make HP = B

2. In the following formulas, the unary linear inequality is () a.x ≥ b.2x > 1-x2 c.x + 2Y

Choose D
A no, it's not an inequality
B no, it's a quadratic inequality of one variable
C is not. It's a quadratic inequality of two variables
D is