7.
If the abscissa of a point is x and the ordinate is y, then (x, y) are called the coordinates of
the point.
8. The coordinates of a point on the x-axis are of the form (x,0) and that of the point on the
y-axis are (0,y).
Please explain me this points..
Answers
Step-by-step explanation:
I can try to make things clearer to you.
suppose you are outside your home and want to tell your friend the location of a ball you have kept in your home. how would you do that? you would try to be as accurate as possible like look below the bed in my room or in the upper rack of the cupboard of my room. If you don't give more accurate position of the ball, it will be very difficult for your friend to locate the ball in your home.
In real life we can cope with less or no accuracy, but in math you need to be 100% accurate in describing the location.
Now suppose you make a point on a blank page. how would you tell your friend by talking over phone the exact location of the point so that your friend may be able to mark a point on a similar page exactly on the same position that you have made. Even if you send a picture of your page containing the point on whatsapp or other means, do you think your friend will be able to locate the point by seeing the image? absolutely not, unless he is able to measure length and breadth of page and position of point w.r.t sides of the page.
If you understand coordinate, you can tell your friend over phone that take a blank page of A4 size (A4 size paper has fixed length and breath), measure 7 cm from bottom left corner on the bottom side of the page and then measure 9 cm on the upside parallel to left side of the page. In this way you have communicated the coordinates of the point to your friend and he will be able to draw point at the same spot ( ignoring the errors that happens in measurements)
Similar system has been evolved to locate apoint in two or three dimensional space
Two mutually perpendicular lines are drawn just like sides of pages. The lines are called axes. the horizontal line is called x-axis and vertical line is called y-axis.
X-axis and Y-axis are basically number lines joined perpendicularly at zero.
The intersection point of the axes is called origin and its value is 0,0).
To locate a point we first move towards x axis and reach exactly beneath the point. Then we proceed along y axis until we reach the point.
the distance covered along x axis is also called abscissa and distance covered along y axis is called ordinate.
The position of the point is described as an ordered paid (x,y). this indicates that we have to move x unit along x axis and y unit along y axis. x and y can be any number. the ordered pair (x,y) or (a,b) whatever the value is called coordinate of a point.
,Thus you can easily see that if a point lies on x axis, to reach there we need to move only along x axis and not along y axis. in such case y=0 and cordinate is (x,0).
similarly, if a point is on y axis it's cordinate will be (0,y) because we do not need to move along x axis...
Hope this is helpful for you.