CH – COORDINATE GEOMETRY

[Audio] Good morning everyone and welcome to my presentation I Altuf SIDDIQUI going to present the mathematics chapter– COORDINATE geometry well what do you meant by coordinate geometry A coordinate geometry is a branch of geometry where the position of the points on the plane is defined with the help of an ordered pair of numbers also known as coordinates. Then Cartesian plane A cartesian plane is a 2D plane which is formed by the intersection of two perpendicular lines known as the x-axis and y-axis. This formula is used to find the coordinates at which a line is divided into two equal halves.

[Audio] Now what is origin The point at which the two axes intersect is called the origin. The origin is at 0 on the x-axis and 0 on the y-axis. Then graph quadrant The two intersecting lines in the Cartesian plane make four distinct graph quadrants. This x-axis and y-axis of a graph divide it into four quadrants. Moreover, each quadrant includes a combination of positive and negative values for coordinates x and y. Points in Different Quadrant Signs of coordinates of points in different quadrants: Quadrant 1 : (+x, +y) Quadrant 2 : (-x, +y) Quadrant 3 : (-x, -y) Quadrant 4 : (+x, -y) See in figure.

[Audio] Now we are going to read about abscissa and ordinate what is abscissa Abscissa is the distance from a point to the vertical or y -axis, measured parallel to the horizontal or x - axis. It is also known as the x –coordinate then what is ordinate Ordinate is the distance from a point to the horizontal or x -axis, measured parallel to the vertical or y -axis. It is also known as the y -coordinate. Now what is slope of a line The slope of a line is defined as the change in y coordinate with respect to the change in x coordinate of that line. The net change in y coordinate is Δy, while the net change in the x coordinate is Δx. So the change in y coordinate with respect to the change in x coordinate can be written as, m = Δy/ Δx where,m is the slope Note that tan θ = Δy/Δx We also refer this tan θ to be the slope of the line. See in figure.. Maded by MOHD. ALTUF . SIDDIQUI CLASS 9TH –F ROLL NUMBER 20.