Have a question?
Message sent Close
Quadrilaterals and ...
 
Notifications
Clear all

Quadrilaterals and Polygons

98 Posts
20 Users
6 Reactions
32.4 K Views
0
Topic starter

 Hello sir,

Please solve the following question

 

Anonymous 23/03/2018 1:08 pm

Hello Ananya 

Please find the solution

49 questions & discussions are there under this sub-topic
2

If the diagonals of a rhombus of side 20cm are in the ratio of 3:4, then what is the area (in sq.cm) of the rhombus?

Sachin Yadav 24/01/2024 4:28 pm

@neraj-naiyar sir,

Side of the rhombus = 20 cm

Let the diagonals be 4x and 3x. They bisect each other at right angles, thereby creating 4 identical right angled triangles, with hypotenuse 20 cm.

In a single right angled triangle,

20² = (4x/2)²+(3x/2)²

400 = 4x² + (9/4)x²

400 = (25/4)x²

x=8

Total area =(1/2)(4x)(3x) = (1/2)(32)(24) = 384cm²

2

Q1.  Let T be the triangle formed by the straight line 3x + 5y - 45 = 0 and the coordinate axes. Let the circumcircle of T have radius of length L, measured in the same unit as the coordinate axes. Then, the integer closest to L is  

This post was modified 1 year ago by Sachin Yadav
Neraj (TG) 28/01/2024 5:57 pm

@sachin-yadav 

 

28

 

28 1
2

Q1.  If the rectangular faces of a brick have their diagonals in the ratio 3 : 2 3 : 15, then the ratio of the length of the shortest edge of the brick to that of its longest edge is?

A. 1 : 3
B. 2 : 5
C.2 :3

D. √3 : 2

Madhav 06/02/2024 2:34 pm
This post was modified 1 year ago by Madhav
0

ABCD is a trapezium, in which AD and BC are parallel. If the four sides AB, BC, CD and DA are respectively 9cm, 12cm, 15cm and 20cm then the magnitude of the sum of the squares of the two diagonals is:

(a) 638 (b) 786 (c) 838 (d) 648

0

Let the height be h. Base be 20 top be 12.

Draw perpendiculars from the edges of the top to the base.

We have left overs of the base on both the sides. call them x and y.

Now X+Y =8 

Now sum of the diagonals is nothing but h^2 + (20-y)^2 + h^2 + (20-x)^2

it comes out to be 800-40(x+y)+2 h^2 + X^2 + Y^2

We have h^2+X^2 = 9^2 and h^2+ Y^2 = 15^2 and X + Y = 8

Ans = 786. 

0
Topic starter

Hello sir,

Please solve this question:

ABCD is a trapezium, such that AB, DC are parallel and BC is perpendicular to them. If angle DAB = 45o, BC = 2 cm and CD = 3 cm then AB = ?

(A) 5 cm (B) 4 cm

(C) 3 cm (D) 2 cm

Anonymous 05/04/2018 6:19 pm

Hello Ananya,

 

Please find the attachment.

Draw DE perpendicular on AB,

CD = BE= 3 cm,

AE = ED = 2 cm.

AB = AE + EB = 2 + 3 = 5 cm

0
IMG 20180709 220747

Find the value of x

TG Team 10/07/2018 12:41 am

∆DOC ~ ∆BOA 

 

DO / OC= BO/ OA 

 

3/6 =( x - 4)/(x -3) 

 

3x - 9 = 6x - 24 

 

x = 5 

0

Could you please solve this question?

WhatsApp Image 2018 07 20 at 11.07.24 PM
TG Team 21/07/2018 11:17 am

Hello Vernica , 

PFA the solution. 

1111
0

A dog is tied to the corner of a house with a regular hexagonal base that measures 6 ft on each side. If the rope is 12 ft in length, what is the area in square feet of the region outside the house that the dog can reach?

TG Team 25/07/2018 11:40 pm
This post was modified 7 years ago by TG Team

Hello Richa ! 

The area of the region outside the house that the dog can reach = Shaded area shown in the figure =  π(12^2 ) x 240/360 + π ( 6^2) x 120/360 = 108π 

Capture
0

Both the questions, please.

2
TG Team 25/07/2018 11:03 pm

3. 

 

AB = OP ( Diagonals of a rectangle ) 

 

OP = r = 36 

 

Diameter = 2r = 72in

 

IMG 20180725 225547
Richa 26/07/2018 12:02 am

Thankyou, Sir. Can you also share the solution for Q4 in the same image?

 

0

Hey sir, posting a question below. Though I've solved the question with the approach mentioned in the image (solution with blue pen), but is there any way to solve it faster? If somehow we could prove triangle PBC as a right angled triangle, it's just a 10sec question. But my question is, how could we do that?

IMG 20180726 002605
TG Team 26/07/2018 4:58 pm

Hello Richa ! 

Rotate P to P' 90 degrees with centre B . 

We get PP' = 6√2 

So BPP' = 45 degrees 

Now cosP'PC = √2/2

cosP'PC = 45 degrees too. 

So , Area = BC^2 = 14^2 + 6^2 = 232 . 

0

Hello Sir, please help.

new
TG Team 27/07/2018 7:03 pm
This post was modified 7 years ago by TG Team

Hello Richa, 

PFA the solution. 

and please do not post/discuss the questions ( from copy CAT -1)  till the window of the test (Copy CAT -1)  is not closed.

Geo Solution
Richa 27/07/2018 7:26 pm

Ok, Sir. I'll keep that in mind. 

0

In regular octagon ABCDEFGH
Find the area of ACEG, if side of octagon is 2 cm
A. 13.24
B.12.97
C.14.18
D 13.66

TG Team 01/08/2018 12:32 pm

Hello Richa 

 

PFA the approch 

 

IMG 20180801 122300
0
IMG 20180802 173920

 

Sir please help

TG Team 02/08/2018 6:32 pm

Triangle MEC  ~ Triangle BEA 

Area MEC / Area BEA = MC²/AB² = 1²/2² 

If , Area MEC = x then Area AEB = 4x 

EC : AE = 1  : 2 hence area BEC = 2x 

Area [Square ABCD] = 2 [ Area ABC] = 12x 

Area AEMD = 12x - 2x - x - 4x = 5x 

Required ratio : x : 5x = 1: 5 

Page 1 / 4