ch 1.1 Distance Between Two Points两点之间的距离.ppt

What is the meaning of this sign? Icy Road Ahead Steep Road Ahead Curvy Road Ahead Trucks Entering Highway Ahead What does the 7% mean? 7% is the gradient of the road. It means the road drops 7 feet vertically for every 100 feet horizontally. 7% So, what is gradient ??? 7 feet 100 feet Gradient is the ratio of the vertical rise to the horizontal run between any two points on a line. Usually referred to as the rise over run. Gradient can be expressed different ways: 1) Find the gradient of the line that passes through the points (-2, -2) and (4, 1). When given points, it is easier to use the formula! y2 is the y coordinate of the 2nd ordered pair (y2 = 1) y1 is the y coordinate of the 1st ordered pair (y1 = -2) * * * 7.1 Midpoint of the Line Joining Two Points Objectives In this lesson you will learn how to find the midpoint of a line segment and apply it to solve problems. * Page 138 * Example 4 Page 140 * Exercise 7.1 Page 140 Question 3 * Exercise 7.1 Page 141 Question 4 * Example 4 Page 140 Coordinates ,points and lines 1.1 The distance between two points 1.2 The mid-point of a line segment 1.3 The gradient of a line segment Y-axis X-axis Origin(0,0) Cartesian coordinates system Where are you? 1.1 The distance between two points Coordinate Geometry 2 -7 -6 -5 -4 -3 -2 -1 1 5 7 3 0 4 6 8 7 1 2 3 4 5 6 8 -2 -3 -4 -5 -6 -7 Lets find the distance between two points. So the distance from (-6,4) to (1,4) is 7. If the points are located horizontally from each other, the y coordinates will be the same. You can look to see how far apart the x coordinates are. (1,4) (-6,4) 7 units apart 2 -7 -6 -5 -4 -3 -2 -1 1 5 7 3 0 4 6 8 7 1 2 3 4 5 6 8 -2 -3 -4 -5 -6 -7 What coordinate will be the same if the points are located vertically from each other? So the distance from (-6,4) to (-6,-3) is 7. If the points are located vertically from each other, the x coordinates will be