a triangle and a parallelogram are drawn on the same base and between the same parallels, then the area of the triangle is equal to half the area of the parallelogram and Triangles drawn on the same base and between the same parallel lines are equal in areaIn △ABC, D is the mid-point of AB.P is any point on BC.CQ∥PD meets AB in Q and ar(△BPQ) = y ⋅ ar(△ABC). Then the value of y is?Select an answer
Question
a triangle and a parallelogram are drawn on the same base and between the same parallels, then the area of the triangle is equal to half the area of the parallelogram and Triangles drawn on the same base and between the same parallel lines are equal in areaIn △ABC, D is the mid-point of AB.P is any point on BC.CQ∥PD meets AB in Q and ar(△BPQ) = y ⋅ ar(△ABC). Then the value of y is?Select an answer
Solution
The problem states that triangle BPQ and triangle ABC are drawn on the same base and between the same parallels. According to the property of triangles, the area of triangle BPQ is half the area of parallelogram BQCP.
Since D is the midpoint of AB, triangle BPD is similar to triangle BQC (by AA similarity as ∠B is common and ∠PBD = ∠QBC because they are alternate angles as PD is parallel to CQ).
Since the triangles are similar, the ratio of their areas is equal to the square of the ratio of their corresponding heights. But in this case, since D is the midpoint of AB, the height of triangle BPD is half the height of triangle BQC. Therefore, the area of triangle BPD is one-fourth the area of triangle BQC.
Now, triangle BPQ is composed of triangle BPD and triangle DPQ. Since triangle DPQ is identical to triangle BPD (as D is the midpoint of AB), the area of triangle BPQ is twice the area of triangle BPD.
Therefore, the area of triangle BPQ is half the area of triangle BQC, which is the same as saying that the area of triangle BPQ is y times the area of triangle ABC.
So, y = 1/2.
Similar Questions
If a triangle and a parallelogram are drawn on the same base and between the same parallels, then the area of the triangle is equal to half the area of the parallelogram and Triangles drawn on the same base and between the same parallel lines are equal in area ABCD is a trapezium in which AB∥CD and DC = 40cm and AB = 60cm. If X and Y are respectively the mid-points of AD and BC, ar(trap .DCYX) = p × ar (trap. XYBA). Find the value of p.
3.In a parallelogram ABCD, E is the midpoint of CD . Find the ratio between the area of △ABE and area of Parallelogram ABCD .
In the given figure, if area of the parallelogram ABCD is 30cm2 , then ar(△ADE) + ar(△BCE) is equal to:
Look at the image below. Find the area of the parallelogram
ABCD is a parallelogram of area "S". E and F are the mid points of the sides AD and BC respectively. If G is any point on the line EF. then the area of ΔAGB is equal to
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.