1. IGCSE Revision Lesson 3 I can calculate the gradient of a straight line from the co-ordinates of two points on it I can calculate the length and the co-ordinates of the midpoint of a straight line segment from the co-ordinates of its end points I can estimate gradients of curves by drawing tangents

2. Distance between two coordinates e.g. find the distance between (3, -2) and (6, 2) (3, -2) (6, 2) General formula for distance (x 1, y 1 ) (x 2, y 2 )

3. Midpoint of two coordinates e.g. find the midpoint between (3, -2) and (6, 2) (3, -2) (6, 2) 4 4 2 2 General formula for midpoint (x1, y1) (x2, y2)

4. Finding the gradient of a straight line Gradient = for every one square moved to the right, how many moved up? OR – difference in y dy difference in x dx

5. Finding the gradient of a straight line For two points (1,2) and (2, 5)? a)(3, 2) (4, 4) b)(2, 5) (4, 11) c)(-1, 2) (3, -2) d)(-2, 2) (-4, 3)

6. Drawing a tangent to estimate a gradient