Geometry: Key Theorems & Formulas
Master the essential theorems and formulas of Geometry with this focused flashcard deck. Covering everything from basic shapes like triangles and circles to polygons and 3D solids, these cards are designed to reinforce key concepts for your exams. Use them to quickly recall definitions, properties, and calculation methods vital for success in Geometry.
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What is the sum of a triangle's interior angles?
180°.
What is the Pythagorean theorem?
In a right triangle, a² + b² = c², where c is the hypotenuse.
What is the area of a triangle?
½ × base × height, with the height perpendicular to the base.
What is the area of a parallelogram?
Base × perpendicular height.
What is the area of a trapezoid?
½ × (base₁ + base₂) × height, where the bases are the parallel sides.
What is the circumference of a circle?
C = 2πr = πd.
What is the area of a circle?
A = πr².
What is the volume of a cylinder?
V = πr²h.
What is the volume of a sphere?
V = (4/3)πr³.
What is the volume of a cone?
V = (1/3)πr²h.
What is the sum of the interior angles of an n-sided polygon?
(n − 2) × 180°.
Parallel lines are cut by a transversal. How are alternate interior angles related?
They are congruent.
What is the triangle inequality theorem?
Any two sides of a triangle add up to more than the third side.
What is the distance formula?
d = √((x₂ − x₁)² + (y₂ − y₁)²).
What is an inscribed angle's relationship to its arc?
It is half the measure of its intercepted arc.