COORDINATE GEOMETRY (A) Main Concepts and Results
Cartesian system Coordinate axes Origin
Quadrants
Abscissa
Ordinate
Coordinates of a point Ordered pair
Plotting of points in the cartesian plane:
• In the Cartesian plane, the horizontal line is called the x-axis and the vertical line
is called the y-axis,
• The coordinate axes divide the plane into four parts called quadrants,
• The point of intersection of the axes is called the origin,
• Abscissa or the x-coordinate of a point is its distance from the y-axis and the ordinate or the y-coordinate is its distance from the x-axis,
• (x, y) are called the coordinates of the point whose abscissa is x and the ordinate is y,
• Coordinates of a point on the x-axis are of the form (x, 0) and that of the point on the y-axis is of the form (0, y),
CHAPTER 3
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COORDINATE GEOMETRY 25
• The coordinates of the origin are (0, 0),
• Signs of the coordinates of a point in the first quadrant are (+, +), in the second quadrant (–, +), in the third quadrant (–, –) and in the fourth quadrant (+, –).
(B) Multiple Choice Questions
Write the correct answer :
Sample Question 1: The points (other than origin) for which abscissa is equal to the ordinate will lie in
(A) I quadrant only (B) I and II quadrants
(C) I and III quadrants (D) II and IV quadrants Solution : Answer (C)
EXERCISE 3.1
Write the correct answer in each of the following : 1. Point (–3, 5) lies in the
(A) first quadrant (B) second quadrant
Answer:
x=5
y=25
Step-by-step explanation:
You can start by finding the value of x. Since opposite angles in a parallelogram are equal, 11x=55 and x=5. Since adjacent angles are supplementary, 5y+55=180, 5y=125 and y=25. Hope this helps!
We find the slope through the formula y2-y1/x2-x1
so when we plug in the values of our two points, we get
2-(-1)/(0-(-1))
this gets us 3/1
Which gives us the slope m=3
Well I’m just trying to get points for this thing but idk
