Tag: when lines join

Questions Related to when lines join

$ABCD$ is a trapezium in which $AB\parallel CD$. Which of the following is equal to $AC^{2}+BD{2}$?

  1. $AD^{2}+BC^{2}-2AB.CD$

  2. $AD^{2}+BC^{2}+2AB.CD$

  3. $AD^{2}-BC^{2}+2AB.CD$

  4. $AD^{2}-BC^{2}-2AB.CD$


Correct Option: A

In trapezium PQRS, PQ($23$cm) and RS($13$ cm) are the bases. Find the area of the trapezium if the diagonals bisect angles SPQ and PQR.

  1. $350$ $cm^2$

  2. $276$ $cm^2$

  3. $216$ $cm^2$

  4. $410$ $cm^2$


Correct Option: B

$ABCD$ is a trapezium in which $BC \parallel AD, BC=20\ cm$ and $AD=45\ cm$. If $P$ and $Q$ are the midpoints of $AB$ and $CD$ respectively, then the ratio of $ar(\Box PBCQ)$ to $ar(\triangle PQD)$ is

  1. $\dfrac{42}{13}$

  2. $\dfrac{13}{6}$

  3. $\dfrac{21}{13}$

  4. $\dfrac{13}{7}$


Correct Option: A

In trapezium $PQRS$, side $PQ\parallel SR$. Diagonals $PR$ and $QS$ intersect each other at point $M$.  $PM=3RM$ 

  1. True

  2. False


Correct Option: B

The area of a trapezium is  $385 { cm } ^ { 2 } .$  Its parallel sides are in the ratio  $3 : 4$  and the perpendicular distance between them is  $11 { cm } .$  Its longer side is

  1. $35 cm$

  2. $30 cm$

  3. $40 cm$

  4. $60 cm$


Correct Option: A

In a trapezium, the lengths of its parallel sides are $a$ and $b$. The length of the line joining the midpoints of its non-parallel sides is :

  1. $\dfrac{a-b}{2}$

  2. $\dfrac{a+b}{2}$

  3. $\dfrac{ab}{2}$

  4. $\dfrac{ab}{a+b}$


Correct Option: A

Find the height of a trapezium whose area is  $68 { cm } ^ { 2 }$  and whose bases are  $13 { cm }$  and  $26 { cm }.$

  1. $\dfrac { 15 }{ 16 } { cm }$

  2. $\dfrac { 9 }{ 8 } { cm }$

  3. $\dfrac { 10 }{ 3 } { cm }$

  4. $\dfrac { 9 }{ 5 } { cm }$


Correct Option: A

State true or false:

In trapezium $ ABCD  $, $ AB  $ is parallel to $ DC  $; $ P  $ and $ Q  $ are the mid-points of $ AD  $ and $ BC  $ respectively. $ BP $ produced meets $ CD $ produced at point $ E $. Hence, $ PQ $ is parallel to $ AB $

  1. True

  2. False


Correct Option: A
Explanation:

Given: ABCD is a trapezium. $AB \parallel DC$. P and Q are mid points of AD and BC respectively.
BP produced meets CD at E

Construction: Join BD. Draw a parallel line from P which meets BD on M such that $PM \parallel AB$ and a parallel line from Q which meets BD on N such that $QN \parallel CD$

Now, In $\triangle ADB$
P is mid point of AD and $PM \parallel AB$. Thus, M is mid point of BD.

In $\triangle BDC$
Q is mid point of BC and $QN \parallel DC$. Thus, N is mid point of BD

Hence, M and N are same points. Thus, PM or QN is a straight line, PQ
and $PQ \parallel AB \parallel DC$

State true or false:

In trapezium $ ABCD  $, $ AB $ is parallel to $ DC $;  $ P $ and $ Q  $ are the mid-points of $ AD  $ and $ BC  $ respectively. $ BP $ produced meets $ CD $ produced at point $ E $. Hence, point $ P  $ bisects, 

  1. $ BE  $

  2. $ AB  $

  3. $ BC  $

  4. none of the above


Correct Option: A
Explanation:

Given: ABCD is a trapezium. $AB \parallel DC$. P and Q are mid points of AD and BC respectively.
BP produced meets CD at E

To prove: P is mid point of BE.
In $\triangle APB$ and $\triangle EPD$
$\angle APB = \angle EPD$ (Vertically opposite angles)
$\angle EDP = \angle PAB$ (Alternate angles)
$PA = PD$ (P is mid point of AD)
Thus, $\triangle APB \cong \triangle DPE$ (ASA rule)
Hence, $PE = PB$ (By cpct)
thus, P is mid point of BE

In a trapezium ABCD, side AB is parallel to side DC; and the diagonals AC and BD intersect each other at a point
Such that:
$\displaystyle PA\times PD= PB\times PC.$

  1. True

  2. False


Correct Option: A
Explanation:

In $\triangle$ APB and $\triangle$ CPD,
$\angle APB = \angle CPD$ (Vertically opposite angles)
$\angle ABP = \angle CDP$ (Alternate angles of parallel sides AB and CD)
$\angle BAP = \angle DCP$ (Alternate angles of parallel sides AB and CD)
Hence, $\triangle APB \sim \triangle CPD$ (AAA rule)
Thus, $\frac{PA}{PC} = \frac{PB}{PD}$
$PA \times PD = PB \times PC$