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There is a 24 cm long, 18 cm wide rectangular iron sheet, which is welded into a box without a cover by subtracting the square with a side length of 4 cm from the four corners, What's the surface area of this box
Surface area = 24 × 18-4 × 4 × 4 = 368 square centimeter
A piece of cardboard cut four small square pictures with side length of 5cm, length of 32cm, width of 24cm can be made into a box without cover. What's the volume of this box?
You can't make a small box with four small squares. You must make five small squares to make a small box without a cover
One bottom edge of a parallelogram is 12cm, and the height of the two bottom edges is 10cm
44 cm
Given that O is the diagonal of a parallelogram, AC = 10cm, BD = 18cm, ad = 12cm, then the perimeter of △ BOC is
According to the meaning of the title, we can draw a conclusion
The circumference of △ BOC is:
OB+OC+BC
=(1/2)BD+(1/2)AC+AD
=9+5+12
=26
thank you
What's the change of perimeter and area when the rectangular wooden frame with length of 12cm and width of 10cm is drawn into a parallelogram?
The circumference is the same, because the four sides are the same
If the area becomes smaller and a diagonal line is added, the area of a triangle is 1 / 2 * 10 * 12 * sinc (C is an inner angle of a parallelogram). Because C ∈ (0 ° 180 °), when C = 90 °, sinc = 1 is the largest, that is to say, when a parallelogram is a rectangle, the area is the largest
The perimeter of parallelogram is 12cm at the bottom, 6cm at the height and 8cm at the height
zc727,
The area of parallelogram is:
12 × 6 = 72 (cm2)
The other bottom edge is:
72 △ 8 = 9 (CM)
The perimeter is:
(12 + 9) × 2 = 42 (CM)
The perimeter of a rectangle is 24cm. If its length and width increase by 3cm, how many square centimeters will its area increase
Let length a, width B and perimeter 24
24 = 2 * (a + b) so a + B = 12
Original area = a * B
Area after deformation = (a + 3) * (B + 3) = AB + 3A + 3B + 9
Area increase 3A + 3B + 9 = 3 * (a + b) + 9
=36+9
=45
So the area is increased by 45
A rectangle 8 cm long and 5 cm wide, cut off the largest square, what is the perimeter of the remaining figure?
The rest is a rectangle 5 cm long and 3 cm wide
The circumference is (5 + 3) × 2 = 16 cm
Cut the biggest square out of a rectangle 8 cm long and 5 cm wide. What's the square? What's the perimeter of the remaining figure?
The side length is 5,16
Cut a small square with a side length of 3cm in a rectangle with a length of 10cm and a width of 8cm. How can you cut it? What is the perimeter of the remaining figure?
There are two known methods: one is to cut from a corner of a rectangle, and the perimeter is constant; the other is to cut from an edge of the rectangle. The perimeter becomes larger. But there is a question, if you cut from the middle of the rectangle, how to calculate its perimeter, and what part is the perimeter?
You are very imaginative and have the taste of brain twirling. You are right in two ways, one is perimeter increasing, the other is perimeter unchanged. If you cut in the middle, the perimeter will not change. Here is the definition of perimeter: the length integral around the edge of a limited area is called perimeter. The length of a graph is the perimeter of the graph
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