Simple operation: (7 / 9 + 3 / 4-1 / 6-7 / 18) 1 / 36,2 / 5 * 5 / 9 / (2 / 5-4 / 15)

Simple operation: (7 / 9 + 3 / 4-1 / 6-7 / 18) 1 / 36,2 / 5 * 5 / 9 / (2 / 5-4 / 15)

（7/9+3/4-1/6-7/18）÷1/36
=（7/9+3/4-1/6-7/18）×36
=7/9×36+3/4×36-1/6×36-7/18×36
=28+27-6-14
=25
2/5*5/9/（2/5-4/15）
=2/9/（2/15）
=2/9×15/2
=5/3

Given the square of a + 4AB + 4B = 1, then a + 2B

What is 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9. + 100

5050

Substitution method for solving binary linear equations
3X+4Y=16
5X-6Y=33
I don't use braces. That's the equations
Please write down the procedure specification completely~

X = (16-4y) / 3 is obtained from (1)
Substituting it into 2 gives 5 (16-4y) / 3-6y = 33
So y = - 1 / 2
Substituting it into (1) gives x = 6
So x = 6, y = - 1 / 2
Method 2
Multiply both sides of the equal sign by 3 / 2
① The formula becomes (9 / 2) x + 6y = 243
The formula 3 + 2 is equal to 5x + (9 / 2) x = 57, and the solution is x = 6
Substituting x = 6 into Formula 1, we get 18 + 4Y = 16 and y = - 1 / 2

My father is 28 years older than Xiao Liang. Seven years later, my father's age is just three times that of Xiao Liang. How old are my father and Xiao Liang after seven years?

A: seven years later, my father will be 42 years old and Xiao Liang will be 14 years old

A cuboid cistern is 40 meters long, 18 meters wide and 4.5 meters deep. If cement is applied around and at the bottom of the cistern, how many square meters is the area of cement applied
How many cubic meters can the pool store water at most?

How many square meters is the area of plastering cement? In fact, it is the surface area - length * width
How many cubic meters can this pool store water at most
Because "40 meters long, 18 meters wide, 4.5 meters deep"
So surface area length width = 2 (40 * 18 + 40 * 4.5 + 18 * 4.5) - 40 * 18 = 1242 (M2)
Volume = 40 * 18 * 4.5 = 3240 (M3)

12 divided by 5 = 6:10 = 35 parts () = 35 parts = (): 15
12 divided by 5 = 6:10 = 35 parts () = 35 parts = (): 15

12 divided by 5 = 24:10 = (175 of 12) = (84 of 35) = 84 of 35 = (36): 15

The length of one side of a triangle is 18cm. To make its area not larger than the area of a square with 5cm side length, the value range of the height of the known side of the triangle is obtained

18h/2≤5*5
h≤25/9
0＜h≤25/9

X divided by 1.2-15 = 5 equation

24

The radius of a circle is 4dm, the perimeter is () decimeter and the area is () square decimeter after expanding by 4:1

The radius of a circle is 4dm, the perimeter is (100.48) decimeters, and the area is (803.84) square decimeters
16 × 2 × 3.14 = 100.48 decimeters
16 × 16 × 3.14 = 803.84 square decimeter