X △ 0.5 = 25 to solve the equation

X △ 0.5 = 25 to solve the equation

x=25×0.5
x=12.5

(180-x)*15=12*x.

15(180-X)=12X
2700=27X
X=100
This is my conclusion after meditation,
If not, please ask, I will try my best to help you solve it~
If you are not satisfied, please understand~

Solution equation: 180-x + (90-x) = 180

Remove brackets
180-x+90-x=180
transposition
180+90-180=x+x
Merge congeners
90=2x
That is, 2x = 90
Divide two sides by two
x=90÷2
x=45

Xiao Ming bought a bag of flour in the supermarket. The bag was marked with the words of [25 ± 0.3] kg. What does "± 0.3 kg" mean? Xiao Ming weighed it and found that it was only 24.8 kg. Did the flour factory cheat?

At least 25-0.3 = 24.7 > 24.8
So there's no fraud

-0.0000025 is expressed by scientific notation as______ ．

-0.0000025 = - 2.5 × 10-6, so the answer is: - 2.5 × 10-6

It's the one at the beginning. I want the speed point that has been written,
Chen Ming and I are good friends. One day, we took out a small wooden boat made in the manual group to play. Chen Ming accidentally broke my boat. In the dispute, Chen Ming broke it again. I was very angry and grabbed his boat
That's all in the beginning. It should be longer
I want to be long, about 600 words! If it's really good, I'll score again

Every time I see the exquisite wooden boat hidden in the drawer, I think of Chen Ming. When I was in the first grade of primary school, Chen Ming and I were classmates. Our two families were very close. Every day we went to school, went home, and reviewed our lessons together. We became inseparable friends until the fourth grade

In rectangular ABCD, ab = 4cm, BC = 3cm, there is a moving point P moving from point B, BC, CD, DA at the speed of 1cm per second, taking point a as the coordinate origin, and taking AB as the coordinate origin
CD establishes a plane rectangular coordinate system for x-axis and y-axis
1. When the area of triangle ABP is equal to 5 square centimeters, the time t of point P moving is calculated
2. When point P moves for T seconds, the algebraic expression of T is used to express the area of triangle ABP

Let P (x, y) ∵ s △ ABP = 1 / 2Ab * y = 5; ab = 4 ∵ y = 5 / 2, when p is on BC, t = 5 / 2 ∵ 1 = 5 / 2 = 2.5, when p is on ad, t = (3 + 4 + 3-5 / 2) / 1 = 7.5, that is, when t = 2.5 or 7.5S, the area of triangle ABP is equal to 5 square centimeter

A simple algorithm of 1 / 2 + 3 / 8 + 7 / 8 * 7

4/8+3/8+7/8*7=7/8+7/8*7=7/8*(1+7)=7

How to calculate the chemical reaction rate of grade 2 in senior one

First of all, we have to determine the chemical equilibrium equation, find the concentration of the corresponding substance or the change of the amount of substance, so as to determine the reaction rate

A parallelogram has the same base and height as a triangle. What percentage of the area of the triangle is that of the parallelogram?
The reason should be clear

If a parallelogram and a triangle have the same base and height, then the area of the triangle is 50% of the area of the parallelogram
Let bottom = a, height = H
Parallelogram area = ah
Triangle area = ah / 2
ah/2÷ah=50%