right-angled triangle
Ninety-degree polygon shape
A right-angled triangle has one angle of exactly 90 degrees—a right angle.
The side opposite the right angle is the hypotenuse, always the longest side.
The Pythagorean theorem describes the relationship between its sides: the square of the hypotenuse equals the sum of the squares of the other two sides.
Also called a right triangle.
Longest right-triangle side
- legsLocomotion appendages below torso
- verticesCorner points of shapes
- perpendicularAt right angles
- isoscelesTwo sides match
scalene · congruent · similar · altitude · median · bisector · circumcircle · area
Demonstrated logical conclusion
- PythagorasAncient Greek mathematician
- hypotenuseLongest right-triangle side
- proofDemonstration of truth
- EuclideanFlat-space geometry type
Opposite over hypotenuse
- cosineRatio in triangle math
- tangentLine touching curve once
- oppositeReverse or contrary thing
- adjacentDirectly next to
hypotenuse · secant · cosecant · cotangent · ratio · inverse · arcsin · arccos
Tool for drawing angles
- protractorAngle-measuring instrument
- compassDevice showing cardinal directions
- straightedgeLine-drawing tool
- draftingCreating technical blueprints
carpenter's square · framing square · technical drawing · ruler · T-square · architect · blueprint · CAD
Measuring and charting terrain
- navigationDetermining position and course
- roof pitchSteepness of rooftop slope
- staircaseIndoor flight of steps
- rampSloped connecting surface
ladder · architecture · engineering · slope · grade · GPS
hypotenuse
Longest right-triangle side
- legsLocomotion appendages below torso
- verticesCorner points of shapes
- perpendicularAt right angles
isosceles · scalene · congruent · similar · altitude · median · bisector · circumcircle · area · perimeter
theorem
Demonstrated logical conclusion
- PythagorasAncient Greek mathematician
- hypotenuseLongest right-triangle side
- proofDemonstration of truth
sine
Opposite over hypotenuse
adjacent · hypotenuse · secant · cosecant · cotangent · ratio · inverse · arcsin · arccos · arctan
set square
Tool for drawing angles
- protractorAngle-measuring instrument
- compassDevice showing cardinal directions
- straightedgeLine-drawing tool
drafting · carpenter's square · framing square · technical drawing · ruler · T-square · architect · blueprint · CAD
surveying
Measuring and charting terrain
- navigationDetermining position and course
- roof pitchSteepness of rooftop slope
- staircaseIndoor flight of steps
ramp · ladder · architecture · engineering · slope · grade · GPS