plot points A(1,4) B(-3,1) and C (4,1). Name the figure obtained on joining the points. find the area of the figure obtained
Answers
Given:
plot points A(1,4) B(-3,1) and C(4,1)
To find:
name the figure obtained on joining the points. and find the area of the figure obtained.
Solution:
In a graph, there are 2 lines intersecting one another.
The intersecting point is zero (0). the line going upwards(vertical) is the Y-axis and the line going vertically downwards is Y' - axis.
The line which moves horizontally to the right is the X-axis and the line moving horizontally to the left is X' - axis.
now, plotting the point on the graph
Scale: 1 cm = 1 unit on both ( X and Y)
A(1,4) = place 1 on the X-axis and then moving upward on the 1 line make the dot at the 4th point on the Y-axis. ( first quadrant)
B(-3,1) = minus points come on the X' - axis so we move downwards from zero, as we reach -3, we move upwards on the Y-axis to the 1 point. ( second quadrant)
C(4,1) = moving right on the X-axis we reach point 4, and moving upwards from there we reach point 1 on the Y-axis. ( first quadrant)
Joining the points plotted on the graph, we get a triangle.
area of a triangle= 1/2 * base * perpendicular height
base= 7cm ( point B to C)
perpendicular height = 3cm ( point A to base )
area = 1/2 * 7 * 3
= 10.5 cm