If you are given an angle (Θ) and you must determine the gradient: The tangent of the angle is the gradient of the line: tanΘ = m The equation is given
m is the gradient.
Two points are given
Parallel lines If two lines are parallel, their gradients are the same.
Perpendicular lines If two lines are perpendicular, their gradients are opposite and inverse of one another.
Linear equations If the variable occurs more than once first simplify. The variables must all be taken to one side and then added or subtracted. If the variable occurs in the denominator of a fraction, it must be removed. This is done by multiplying by the variable throughout the equation.
Simultaneous linear equations
Solving simultaneous equations (one linear and one quadratic)