Advertisements
Advertisements
प्रश्न
Find the area of quadrilateral ABCD whose vertices are A(-3, -1), B(-2,-4) C(4,-1) and D(3,4)
उत्तर
By joining A and C, we get two triangles ABC and ACD.
`" let" A(x_1,y_1) = A(-3,-1) , B(x_2,y_2)=B(-2,-4) , C(x_3,y_3) = C(4,-1) and Then D (x_4,y_4)= D(3,4)`
`"Area of " Δ ABC = 1/2[x_1(y_2-y_3)+x_2(y_3-y_1)+x_3(y_1-y_2)]`
`=1/2 [-3(-4+1)-2(-1+1)+4(-1+4)]`
`=1/2 [9-0+12]=21/2 ` sq. units
`"Area of " ΔACD =1/2 [x_1(y_3-y_4)+x_3(y_4-y_1)+x_4(y_1-y_3)]`
`=1/2 [-3(-1-4)+4(4+1)+3(-1+1)]`
`=1/2 [15+20+0]=35/2` sq. units
So, the area of the quadrilateral ABCD is `21/2+35/2=28 `.sq units sq units
APPEARS IN
संबंधित प्रश्न
On which axis do the following points lie?
R(−4,0)
Find the third vertex of a triangle, if two of its vertices are at (−3, 1) and (0, −2) and the centroid is at the origin.
Determine the ratio in which the point (-6, a) divides the join of A (-3, 1) and B (-8, 9). Also, find the value of a.
Find the ratio in which the point P(m, 6) divides the join of A(-4, 3) and B(2, 8) Also, find the value of m.
In what ratio does y-axis divide the line segment joining the points (-4, 7) and (3, -7)?
Points A(-1, y) and B(5,7) lie on the circle with centre O(2, -3y).Find the value of y.
If the points A(4,3) and B( x,5) lie on the circle with center O(2,3 ) find the value of x .
Find the centroid of the triangle whose vertices is (−2, 3) (2, −1) (4, 0) .
Write the perimeter of the triangle formed by the points O (0, 0), A (a, 0) and B (0, b).
Write the condition of collinearity of points (x1, y1), (x2, y2) and (x3, y3).
Find the value of a so that the point (3, a) lies on the line represented by 2x − 3y + 5 = 0
Find the area of triangle with vertices ( a, b+c) , (b, c+a) and (c, a+b).
Find the coordinates of the point which is equidistant from the three vertices A (\[2x, 0) O (0, 0) \text{ and } B(0, 2y) of ∆\] AOB .
The area of the triangle formed by (a, b + c), (b, c + a) and (c, a + b)
If points (a, 0), (0, b) and (1, 1) are collinear, then \[\frac{1}{a} + \frac{1}{b} =\]
Any point on the line y = x is of the form ______.
Ordinate of all points on the x-axis is ______.
Points (1, –1) and (–1, 1) lie in the same quadrant.
The distance of the point (–4, 3) from y-axis is ______.