## Geometry

Parallel lines
Construction of the triangle of the three elements
Triangle
The first sign of equality of triangles
Perpendicular to the line
Medians, altitudes, and angle bisectors
Properties of isosceles triangle
Second characteristic of triangle equality
Third characteristic of triangle equality
Equality criteria for a right-angled triangle
Polygon
Convex polygon
Parallelogram
Parallelogram signs
Trapezoid
Rectangle
Rhombus and square
The concept of polygon areas
Square area
Rectangle area
Parallelogram area
Triangle area
Trapezoid area
Pythagoras' theorem
The inverse of the Pythagoras’ theorem
Defining Similar Triangles
The first sign of similar triangles
Second sign of similar triangles
Third sign of similar triangles
Midline of a triangle
Sine, cosine and tangent of an acute angle of a right-angled triangle
The values of sine, cosine and tangent of angles of 30, 45 and 60
The relative position of a line and a circle
Circle tangent
Degree measure of the arc of the circle
Vector concept
Equality of vectors
Delaying a vector from a given point
The sum of two vectors
Law of vector addition. Parallelogram rule
Subtracting vectors
Product of a real number by a vector
The middle line of a trapezoid
Vector coordinates
Relationship between vector coordinates and coordinates
Equation of a line in a plane
Equation of a straight line
Sine, cosine, tangent
Basic trigonometric identity. Casting formulas
Circumscribed circle