Geometry ch 9 quiz

Triangle Inequality Theorem

The sum of any 2 sides is greater than the 3rd side

Right

sum and product are equal

Acute

Sum is greater than product

Obtuse

Product is greater than sum

45 - 45 - 90 Triangle Theorem

In a 45 - 45 - 90 triangle the

Hypotenuse = Leg x sr2

30 - 60 - 90 Triangle Theorem

In 30 - 60 - 90 triangles

Hypotenuse = 2 x Shorter Leg

Longer Leg = Shorter Leg x sr3

Altitude

Perpendicular line from vertex to opposite side

Right Triangle Similarity Theorem

If the altitude goes to the hypotenuse of a right triangle

All 3 triangles are similar

SOH CAH TOA

She Offered Her Cat A Teaspoon Of Acid (to find side)

Inverse tangent/sine/cosine

To find angle. Tan-1(3/5) = angle A

Area of not right triangle

Area = 1/2bc sin A

Law of Sine

(AAS or ASA) a/Sin A = b/Sin B = c/ Sin C

Law of Cosines

a² = b² + c² - 2bc cos A (SAS or SSS)