ACT Fast Facts - Triangles

Cosecant (csc)

• @@rac{Hypotenuse}{Opposite}@@

• @@rac{Opposite}{Hypotenuse}@@

• @@rac{Adjacent}{Hypotenuse}@@

• @@rac{Hypotenuse}{Adjacent}@@

What is a 30-60-90 Triangle?

• A triangle with angles of 30°, 60°, and 90°

• A triangle with angles of 45°, 45°, and 90°

• A triangle with angles of 60°, 60°, and 60°

• A triangle with angles of 30°, 30°, and 120°

What does SohCahToa represent in trigonometry?

• Sine = Opposite/Hypotenuse

• Cosine = Opposite/Hypotenuse

• Tangent = Adjacent/Hypotenuse

• Sine = Adjacent/Hypotenuse

Sine

• @@\frac{Opposite}{Hypotenuse}@@

• @@\frac{Adjacent}{Hypotenuse}@@

• @@\frac{Opposite}{Adjacent}@@

• @@\frac{Hypotenuse}{Adjacent}@@

Secant (sec)

• SEC = @@\frac{Hypotenuse}{Adjacent}@@

• SEC = @@\frac{Adjacent}{Hypotenuse}@@

• SEC = @@\frac{Opposite}{Hypotenuse}@@

• SEC = @@\frac{Hypotenuse}{Opposite}@@

Cosine

• @@\frac{Adjacent}{Hypotenuse}@@

• @@\frac{Opposite}{Hypotenuse}@@

• @@\frac{Adjacent}{Opposite}@@

• @@\frac{Hypotenuse}{Adjacent}@@

Degrees in a Triangle

• 90°

• 180°

• 360°

• 120°

Pythagorean Theorem

• Use with Right Triangles

• Applicable to All Triangles

• Only for Acute Triangles

• Used in Trigonometry

Tangent

Isosceles Triangle

• Two congruent sides

• All sides are equal

• One angle is 90 degrees

• The sum of angles is 180 degrees