Simply it as follows:
1 + 39 = 40
2 + 38 = 40 etc
18 + 22 = 40
19 + 21 = 40
There are 19 of these plus 40 itself . . .therefore 20 of them
20 x 40 = 800
And finally the last number not used, 20
Therefore 800 + 20 = 820
Answer:
First of all, rectangles and rectangular prisms have one foremost difference, which is their dimensions. A rectangle has two dimensions whilst a rectangular prism has three. Those dimensions include width, length, and height- but a rectangle has only width and length. Although, in comparison, they're both made from the same quadrilateral: rectangles. A "2D" rectangle has one, while a "3D" rectangle, or rectangular prism, is made of six. The rectangles that make up a rectangular prism can also be referred to as faces.
Answer:
centroid is (2,5)
Step-by-step explanation:
