Can be calculated by Pique formula,
The relationship between area s and the number of internal lattice points a and the number of edge lattice points b;
S=a+ b/2 - 1 .
(where A represents the number of points inside the polygon, B represents the number of points on the boundary of the polygon, and S represents the area of the polygon)
s = 12+8/2- 1 = 15
Extended data:
The area of a shape can be measured by comparing a fixed size shape with a square. In the International System of Units (SI), the standard unit area is square meters. A square area with an area of one meter and an area of three square meters will have the same shape as three such squares. In mathematics, the unit square is defined as 1, and the area of any other shape or surface is a dimensionless real number.
There are countless lines bisecting the triangle area. Three of them are the median of the triangle (connecting the midpoint of both sides and the opposite vertex), and they are collinear at the center of gravity of the triangle; In fact, it is the only area bisector passing through the center of gravity. Any line that divides the area and perimeter of a triangle into two halves can pass through the entrance of the triangle (the center of its perimeter). For any given triangle, there are one, two or three triangles.
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