Trigonometry Basics Worksheet

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📐 Part 1: Understanding Right Triangle Parts

1. In a right triangle, the hypotenuse is:

The side opposite the right angle (longest side)

The side next to the angle we're working with

The side opposite the angle we're working with

2. For angle A in a right triangle, the opposite side is:

The side across from angle A

The side touching angle A

Always the longest side

3. The adjacent side is:

The side opposite the angle

The side next to the angle (not the hypotenuse)

Always the shortest side

4. Label the sides of this right triangle for angle θ (theta):

In triangle ABC with right angle at C, if we're finding ratios for angle A:

Hypotenuse: _____________ Adjacent to A: _____________ Opposite to A: _____________

📊 Part 2: Trigonometric Ratios

5. Complete the trigonometric ratio formulas:

sin θ = _________________ ÷ _________________

cos θ = _________________ ÷ _________________

tan θ = _________________ ÷ _________________

6. Memory trick: What does SOH CAH TOA stand for?

7. In a right triangle, the opposite side is 12 cm and the hypotenuse is 15 cm. Find sin θ:

8. If the adjacent side is 8 m and the hypotenuse is 10 m, find cos θ:

🔍 Part 3: Problem Solving

9. A right triangle has sides of 3 cm, 4 cm, and 5 cm. For the angle opposite the 3 cm side:

a) Find sin θ: _____________

b) Find cos θ: _____________

c) Find tan θ: _____________

10. A ladder leans against a wall. The ladder is 13 m long and touches the wall 12 m above the ground. Find the sine of the angle the ladder makes with the ground.

11. Explain in your own words when you would use each trigonometric ratio (sin, cos, tan) to solve a problem:

Trigonometry Basics Worksheet

Trigonometry Basics Worksheet

📐 Part 1: Understanding Right Triangle Parts

📊 Part 2: Trigonometric Ratios

🔍 Part 3: Problem Solving

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