Geometry Unit 5 flashcards - Audrey Beltre

Hypotenuse

a side opposite the 90 degree angle LARGEST SIDE IN A RIGHT TRIANGLE

Leg

The two sides in a right triangle that aren’t hypotenuse

Pythagorean Theorem

Leg²+Leg²=Hypotenuse²

Pythagorean Triple

Three #s that satisfy the Pythagorean theorem (*MUST BE WHOLE NUMBERS*)

Pythagorean Theorem - Classifying Right

if a²+b²=c² its a right triangle

Pythagorean Theorem - Classifying Acute

if a²+b²>c² its acute

Pythagorean Theorem - Classifying Obtuse

if a²+b²<c² its obtuse

45-45-90 Special Right

An isosceles triangle

• two legs are ≅

• The hypotenuse is always the leg multiplied by √2

30-60-90 Special Right

A right triangle

• the shortest leg (opposite 30°) is x

• The longest leg (opposite 60°) is x√3

• The hypotenuse is 2x

Sine

opposite/hypotenuse

Cosine

adjacent/hypotenuse

Tangent

opposite/adjacent

Inverse Sine

sin^-1(opposite/hypotenuse)= ∠θ

Inverse Cosine

cos^-1(adjacent/hypotenuse)= ∠α

Inverse Tangent

tan^-1(opposite/adjacent)= ∠β