If 5x + 2 and - 7 are opposite to each other, then the value of 3x + 5 is

If 5x + 2 and - 7 are opposite to each other, then the value of 3x + 5 is

If 5x + 2 and - 7 are opposite to each other,
Then 5x + 2 = 7
So there are
x=（7-2）/5
=1
There are
3x+5
=3*1+5=8

Equation: X divided by 6 / 7 = 3 / 21

6/7÷x=1/7
x=6/7÷1/7
x=6

Equation [(4 / 9) x + 2] divided by (x + 2) = 9 / 19 how to solve each step of the process!

(4/9x+2)/(x+2)=9/19
4/9x+2=9/19(x+2)
4/9x+2=9/19x+18/19
4/9x-9/19x=18/19-2
-5/171x=-20/19
x=(-20/19)/(-5/171)=36

The length of the vertical line segment between two parallel lines is ()
From one (), two (), form a corner
judge
A ray ()
A flat angle is a straight line ()
It's better to give reasons for the judgment questions

1. The length of the vertical line segment between two parallel lines is (equal)
2. Two rays are drawn from a point to form an angle
judge
If you take any point in a straight line, you can get a ray ((wrong)
Two horizontal angles are a straight line (wrong)
A flat angle is made up of two rays, not a straight line
If you make the concept clear, you will know

(it's better to write the process,
1. When two engineering teams complete a project, team a can complete two fifths of the work in three days: team a and team B work together for three days first, and team B works alone for the rest. How many days can team a and team B work together to complete all the work?
2. The number of people in workshop a and workshop B used to be equal. Due to the need of work, 18 people were transferred from workshop a to workshop B. at this time, the number of people in workshop a is just one fourth of that in workshop B. how many people are there in workshop B now?

1、
A completes 2 / 5 in 3 days, and a completes 2 / 15 every day
In the three days of cooperation, party a completed two fifths, and the remaining three fifths were completed by Party B, sharing nine days,
Therefore, Party B can complete (3 / 5) / 9 = 1 / 15 every day
Cooperation between Party A and Party B needs 1 / (2 / 15 + 1 / 15) = 5 days
2、
The original number of people in workshop a and B is X
that
4（x-18）=x+18
x=30
Therefore, workshop B now has x + 18 = 48 people

What are the square meters and perimeter of 3600 mu of land?

1 mu = 60 square feet = 6000 square feet = 666.666... Square meters
One hectare is equal to 14.999993 mu, i.e. 1 hectare = 15 mu
One hectare is equal to 10000 square meters
One hectare is equal to 100 square meters
3600 △ 15 = 240 hectares, 240 * 10000 = 2.4 million square meters, the perimeter is about 620000 meters

How to do the third question on page 69 of supplementary exercises 4.3 of Mathematics for grade one of Jiangsu Education Press
emergency

Shejia shepherd had x sheep
x＋1=2（x-2-1)
A: x = 7
2 (x-2-1) = 8
Sure. We did

37 times 73 plus 69 times 96 is equal to 9325, similar to the formula of 9325

Sub aa() n = 1 For i = 11 To 99 For j = 11 To 99 a = Left(i, 1) + Right(i, 1) * 10 b = Left(j, 1) + Right(j, 1) * 10 If a * i + b * j = 9325 Then Sheet1.Cells(n, 5) = i Sheet1.Cells(n, 6) = j ...

How many square meters is the door

Measure the width and height and multiply them

Geometric proof
As shown in the figure, in △ ABC, ad is the angle bisector, and ∠ ace is the outer angle of △ ABC. It is proved that ∠ ade = 1 / 2 (∠ B + ∠ ACE)

It is proved that ∵ ad is the angular bisector of ∵ BAC, ∵ bad = ∵ DAC and ∵ ade + ∵ DAC + ∵ ACD = 180 ∵ ade + 1 / 2 ∵ BAC + ∵ ACD = 180 and ∵ ace = ∵ B + ∵ BAC, ∵ BAC = ∵ ace - ∵ B ∵ ade + 1 / 2 (∵ ace - ∵ b) + ∵ ACD = 180 and ∵ ACD + ∵ ace = 18