Tangent | Sine | Cosine | Hypotenuse | Area
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The side lengths of a right-angled
triangle are used to define trigonometric ratios.
Ratio: is the quotient of two numbers.
Quotient: the result of a division.
The tangent is the ratio between the opposite sides
of the hypotenuse (a) and the adjacent side (b).
To find the tangent of any angle on a right-angled
triangle, use the formula T = a/b
The Tangent of
A, B and C are angles on the triangle. a, b, c are the lengths of each side.
If a = 16 and b = 14 divide 16 by 14 to get the tangent of A.
16 ÷ 14 = 1.14 rounded to the nearest hundredth
The Tangent of A = 1.14
The Sine is the ratio between the opposite side (height) (a) and the hypotenuse (c).
To find the sine of any angle on the right-angled triangle, use the formula S = a/c
The Sine of 
A, B and C are angles on the triangle. a, b, c are the lengths of each side.
If a = 16 and c = 18 divide 16 by 18 to get the sine of A.
16 ÷ 18 = 0.89 rounded
to the nearest hundredth.
The Sine of A = 0.89
The Cosine is the ratio between the adjacent side (base) (b) and the hypotenuse (c).
To find the cosine of any angle on the right-angled triangle, use the formula C = b/c
The Cosine of 
A, B and C are the angles on the triangle. a, b, c are the lengths of each side
If b = 14 and c = 18 you would
divide 14 by 18 to get the sine of A.
14 ÷ 18 = 0.78 rounded
to the nearest hundredth.
The Sine of A = 0.78
To find the area of a triangle,
use the formula: A = ½ x b x h
A
= area,
b
= base and
h
= height.
Example:
A triangles base is 3 cm and its height is 5 cm, find the area.
A = ½ x 3 x 5
..=
7.5
Area equals 7.5 cm²
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