It is represented by the equation: x² + y² = 1. The values of x and y are given by trigonometric functions as: x = sin θ y = cos θ So the value of sin θ and cos θ should such that the sum of their squares should be equal to 1. The Slope (m): m = change in y / change in x Equation of a straight line: y = mx Thanks for your support and do visit nitrio.com for more apps for your iOS devices.