How do I find the gradient of a straight line?

• Find two points that the line passes through with coordinates (x₁, y₁) and?(x₂, y₂)
• The gradient between these two points is calculated by

• • This is given in the?formula booklet
• The gradient of a straight line measures its?slope
  • A line with gradient 1 will go up 1 unit for every unit it goes to the right
  • A line with gradient -2 will go down two units for every unit it goes to the right

What are the equations of a straight line?How do I find an equation of a straight line?

• You will need the gradient
  • If you are given two points then first find the gradient
• It is easiest to start with the?point-gradient form
  • then rearrange into whatever form is required
    • multiplying both sides by any denominators will get rid of fractions
• You can check your answer by using your GDC
  • Graph your answer and check it goes through the point(s)

How are the equations of parallel lines connected?

• Parallel lines?are always equidistant meaning they never intersect
• Parallel lines have the same gradient
  • If the gradient of line?l_1?is?m₁?and gradient of line?l_2?is?m_2?then...