plz help
The two points of a triangle are (4,3) and (9,8). The third point lies on the line x-y+3=0. Find the area.
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5 Answers
yagyadutt Mishra
·2010-09-30 00:53:34
It is easy but you have to brush up your mind for few second....
Now here we go :)
Point B = (4,3) Point C = ( 9,8) and Another point A is on x-y+3 = 0
Slope of line BC = (8-3)/(9-4) = 1
Slope of the line on which A is located = 1..
So the line BC is parallel to x-y+3 = 0
So distance between x-y+3 = 0 and the line BC will be the height of the triangle .
Base will be BC
So apply area = 1/2 * base * height
Now equation of BC = > x-y+ c = 0 => x-y-1 = 0
Distance between BC and Line = 4/root(2) = 2√2
Length of BC = √ ( 8-3)^2 + ( 9-4)^2 = 5√2
SO area = 1/2 * 5√2* 2√2 = 10 ans