New posts in euclidean-geometry

What's the measure of the segment HD in the pentagon below?

geometry euclidean-geometry plane-geometry

Why is the area of a circle expressed in $\pi r^2$? [duplicate]

geometry euclidean-geometry

A circle is divided into $5$ parts as shown in the diagram and parts are colored either red or green. Find which area is bigger.

geometry trigonometry euclidean-geometry area

Prove two angles equal in billiard scenario.

geometry euclidean-geometry

Prove that every triangle is the orthogonal projection of an equilateral one

euclidean-geometry transformation

A challenging geometry proof?

geometry proof-writing euclidean-geometry conic-sections

Maximizing an angle based on certain constraints

geometry trigonometry euclidean-geometry circles angle

What's the measure of the segment $PC$ in the pentagon below?

geometry euclidean-geometry plane-geometry

What's the measure of the $\angle x$ in the figure below?

geometry euclidean-geometry plane-geometry

Prove that the angles between tangents to circles centered on a trapezium are equal

geometry euclidean-geometry circles tangent-line

What is view confusion in perspective projection?

geometry euclidean-geometry 3d projective-geometry affine-geometry

Why is "lies between" a primitive notion in Hilbert's Foundations of Geometry?

geometry euclidean-geometry axioms axiomatic-geometry

Hexagon, from vertex to midpoint of a side. [closed]

geometry euclidean-geometry

Find the smallest value of the following expression $\sqrt{(x-9)^2 +4} + \sqrt{x^2+y^2}+ \sqrt{(y-3)^2 +9}$

calculus optimization euclidean-geometry analytic-geometry geometric-inequalities

Parallelogram and vectors

geometry vectors euclidean-geometry quadrilateral

How to determine the bounding curve of a moving circular sector?

geometry euclidean-geometry analytic-geometry problem-solving curves

Find point such that the triangle it makes with two distinct line segments are similar

geometry vectors euclidean-geometry analytic-geometry

Prove that given $r \parallel s$, if t intersects r then it must intersect s

solution-verification euclidean-geometry

Configurations of eleven (or more) points in the Euclidean plane, such that out of any four there is a pair at unit distance.

graph-theory euclidean-geometry combinatorial-geometry plane-geometry

about a ninth-grade geometry problem

geometry euclidean-geometry recreational-mathematics