Use 0, 1, 2, 3. To 9 to form a formula where two three digit numbers add up to four digit numbers. Each digit can only be used once

Use 0, 1, 2, 3. To 9 to form a formula where two three digit numbers add up to four digit numbers. Each digit can only be used once

623+475=1098

Solving binary linear equations by substitution elimination method
{5x-2y=3① 10x-3y=4②

From Formula 1: x = (3 + 2Y) / 5 ③
Substituting formula 2: y = - 2 can be obtained
Substituting y = - 2 into 3 can get x = - 1 / 5
That is, x = - 1 / 5, y = - 2 is the solution of the equations

Grade 6 Volume 2 supplementary exercises of mathematics page 22 questions 3 and 4
3,
Make a square wood block with 10 cm long edge into the largest cylinder. What is the volume of this cylinder?
End at 20.00

Diameter: 10 cm
10 △ 2 = 5cm
5 × 5 × 3.14 = 78.5 square meters
78.5 × 10 = 785 CC
4m = 400cm
Inside: 8 △ 2 = 4cm
4 × 4 × 3.14 × 400 = 20096 CC
Outer: 12 △ 2 = 6cm
6 × 6 × 3.14 × 400 = 45216 CC
45216-20096 = 25120 CC
25120 × 7.8 = 195936 G
195936 g = 195.936 kg

A reservoir is 10 meters long, 4 meters wide and 2 meters deep. Cement is applied to the bottom and around the reservoir. What is the area of cement?

(10 + 4) x2x2 + 10x4 + (10 + 4) x2x2 + 10x4 = 192 square meters, this is the inside and outside together, calculate it!
(it can help you and give me a "high praise". If it's normal, please give me a chance to be adopted!)

5 out of 12 divided by 10 plus 15 divided by 5 out of 6 =?

(5/12/)10+15/(5/6)
=1/24+18
=18 and 1 / 24

Given that the three sides of an isosceles triangle are 5cm, 5cm and 6cm respectively, find the area of the triangle

Let this triangle be ABC, ab = AC = 5, BC = 6, ad ⊥ BC through a to D, then DB = BC / 2 = 3
In the right triangle abd, the hypotenuse AB = 5 and the right side BD = 3. According to the Pythagorean theorem, we can get ad = 4 (3, 4 and 5 are Pythagorean numbers), that is, the height of the triangle ABC on the BC side is 4 and the area of the strand s_ ABC=1/2*BC*AD=1/2*6*4=12

If we divide both sides of the equation 5 (x + 2) = 2 (x + 2) by X + 2, we will get 5 = 2. We know that 5 ≠ 2, so we can guess that x + 2 is equal to 2______ ．

Both sides of equation 5 (x + 2) = 2 (x + 2) divide by X + 2 to get 5 = 2, so x + 2 = 0

The diameter of a circle is 2 decimeters, the area of a half circle is () square decimeters, and the circumference is () decimeters

The diameter of a circle is 2 decimeters, the area of a half circle is (1.57) square decimeters, and the perimeter is (5.14) decimeters

Elementary school grade 6 Volume 1 five simple mathematical problems five simple operations for ratio (Beijing Normal University Edition)
It's better to add 2 more to the application

The ratio is 4:9 0.5:0.15 24:36 2 / 3:8 / 9 0.9:1 / 3

Geometric proof: as shown in the figure, in the isosceles right triangle ABC, ∠ C is a right angle,
P13 62.
As shown in the figure, in the isosceles right triangle ABC, ∠ C is the right angle, the bisector ad of ∠ BAC, the crossing point D is de ⊥ AB, the perpendicular foot is e, and the crossing point E is EF
Verification: AC ^ 2 = 2ef ^ 2
Picture:

Take the midpoint Q of AB and connect CQ
The bisector ad, de ⊥ ab of ∠ BAC is a right angle
So AE = AC
Triangle ACQ and triangle AEF congruence
EF=CQ
AC ^ 2 = AB times AQ = AB times CQ = AB times ef
AC / EF = AB / AC = root 2
AC^2/EF^2=2
AC^2=2EF^2