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Test prep · Math
Geometry Formulas
15 terms · by ineedtostudy · updated 4 hours ago
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Flashcards
Flip through the deck and sort each card into “still learning” or “got it”.
Learn
Adaptive rounds — multiple choice first, then typing, weakest cards more often.
Match
Race the clock pairing terms with definitions. Six pairs a round.
Test
A graded mock exam: written, multiple choice and true/false, marked at the end.
Crossword
Terms become answers, definitions become clues. Solve it here or print it.
Terms in this set
Area of a triangle
½ × base × height
Area of a circle
πr²
Circumference of a circle
2πr, or πd
Area of a trapezoid
½ × (b₁ + b₂) × height
Pythagorean theorem
a² + b² = c², for right triangles only.
Common Pythagorean triples
3-4-5, 5-12-13, 8-15-17, and any multiple of these.
30-60-90 triangle
Sides in ratio 1 : √3 : 2, with the shortest opposite the 30° angle.
45-45-90 triangle
Sides in ratio 1 : 1 : √2.
Volume of a cylinder
πr²h
Volume of a sphere
(4/3)πr³
Surface area of a sphere
4πr²
Sum of interior angles
(n − 2) × 180° for a polygon with n sides.
Slope
(y₂ − y₁) / (x₂ − x₁) — rise over run.
Distance formula
√[(x₂ − x₁)² + (y₂ − y₁)²] — the Pythagorean theorem on a grid.
Midpoint formula
((x₁ + x₂)/2, (y₁ + y₂)/2)