Right Triangle Trig Review

Front

What is a right triangle?

Back

A right triangle is a triangle that has one angle measuring 90 degrees.

Front

What is the Pythagorean theorem?

Back

The Pythagorean theorem states that in a right triangle, the square of the length of the hypotenuse (c) is equal to the sum of the squares of the lengths of the other two sides (a and b): c² = a² + b².

Front

What is the sine function?

Back

The sine function (sin) of an angle in a right triangle is the ratio of the length of the opposite side to the length of the hypotenuse.

Front

What is the cosine function?

Back

The cosine function (cos) of an angle in a right triangle is the ratio of the length of the adjacent side to the length of the hypotenuse.

Front

What is the tangent function?

Back

The tangent function (tan) of an angle in a right triangle is the ratio of the length of the opposite side to the length of the adjacent side.

Front

What is the relationship between sine and cosine?

Back

For complementary angles (A and B where A + B = 90°), sin(A) = cos(B) and cos(A) = sin(B).

Front

What are the side ratios in a 30-60-90 triangle?

Back

In a 30-60-90 triangle, the ratios of the lengths of the sides are 1 : √3 : 2.

Front

What are the side ratios in a 45-45-90 triangle?

Back

In a 45-45-90 triangle, the ratios of the lengths of the sides are 1 : 1 : √2.

Front

How do you find the length of a side using sine?

Back

To find the length of a side using sine, use the formula: opposite = hypotenuse × sin(angle).

Front

How do you find the length of a side using cosine?

Back

To find the length of a side using cosine, use the formula: adjacent = hypotenuse × cos(angle).