More Lessons for Grade 9

Math Worksheets

Videos, worksheets, solutions, and activities to help students learn what is SOHCAHTOA and how to use the trig ratios to find missing sides and missing angles on right triangles.

What is SOH-CAH-TOA?

SOHCAHTOA is a mnemonic to help us remember the trigonometric ratios.

Sine = Opposite/Hypotenuse (SOH)

Cosine = Adjacent/Hypotenuse (CAH)

Tangent = Opposite/Adjacent (TOA)

What is Soh-Cah-Toa?

Shows how to use Soh-Cah-Toa to determine which trig ratio to use.

A basic introduction to defining the three major trigonometric functions (sine, cosine, tangent) are discussed using the mnemonic SOH-CAH-TOA.

A review of basic trigonometry: Sine, Cosine & Tangent including how to use the ratios to find missing sides and missing angles on right triangles.

Students learn that the sine of an angle of a right triangle is equal to the length of the side opposite the angle over the length of the hypotenuse (SOH),

the cosine of an angle of a right triangle is equal to the length of the side adjacent to the angle over the length of the hypotenuse (CAH),

and the tangent of an angle of a right triangle is equal to the length of the side opposite the angle over the length of the side adjacent to the angle (TOA).

Students are then asked to find the values of the sine, cosine, and tangent of given angles in given right triangles.

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