Trigonometry Basics

Subject: Math  ·  Grade level: 10th

Use ratios in right triangles to find missing sides and angles. Trigonometry connects angles to side lengths. With three simple ratios — sin, cos, tan — you c

In this lesson

• Naming the sides
• SOH-CAH-TOA
• Real-world applications

Key terms

Hypotenuse

The longest side of a right triangle, opposite the 90° angle.

Opposite

The side directly across from your reference angle.

Adjacent

The non-hypotenuse side that touches your reference angle.

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