If the diagonal and the area of a rectangle are 25 units and 168 unit

Question

If the diagonal and the area of a rectangle are 25 units and 168 unit^2 respectively, what is the length of the larger side of the rectangle?

A. 12
B. 21
C. 24
D. 25
E. 38

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indu1954 · Answer

Let the length and breadth of the rectangle be ‘l’ and ‘b’ respectively.

(Diagonal)^2 = l^2 + b^2

or, l^2 + b^2 = 25^2 = 625 ………………….(1)

Area of the rectangle = l x b = 168 ……………. (2)

Now, (l + b)^2 = l^2 + b^2 + 2 x l x b = 625 + 2 x 168 = 961

or, l + b = 31 ……………. (3)

Similarly, (l - b)^2 = l^2 + b^2 - 2 x l x b = 625 - 2 x 168 = 289

or, l - b = 17 …………… (4)

Solving (3) and (4), we get :

l = 24 cm

Archit3110 · Answer

168 = 2^3*4*7
digonal = 25 ; 
larger side ; 24^2+7^2 = 625 ; √625 = 25
IMO C

satya2029 · Answer

Since 25^2=X^2+Y^2 and product is 168 last digit is 8 check options 24*7 Perfect C

EgmatQuantExpert · Answer

Solution  
   Given:    
 • The area of a rectangle = 168 square units
• The length of the diagonal = 25 units

To find:    
 • The length of the larger side of the rectangle

Approach and Working Out:    
 • Given,
 o l * b = 168
o  l^2 + b^2 = 25^2

• By simple observation, we can write 168 = 24 * 7 and  25^2 = 24^2 + 7^2 
• Therefore, the length of the rectangle = 24 units

Hence, the correct answer is Option C.

Answer: C

EgmatQuantExpert · Answer

Solution

Given  
 • The diagonal and the area of a rectangle are 25 units and 168 unit^2 respectively

To find  
 • The length of the larger side of the rectangle

Approach and Working out

Let a and b are the sides of the rectangle.
 • a^2 + b^2 = 25^2 = 625
• ab = 168

(a + b)^2 = a^2 + b^2 + 2ab = 625 + 2 * 168 = 625 +336 = 961
 • (a + b) = 31 
(a - b)^2 = a^2 + b^2 - 2ab = 625 +-2 * 168 = 625 - 336 = 289
 • (a - b) = 17

2a = 48, a = 24
 • b = 7

Thus, option C is the correct answer.
   Correct Answer: Option C

exc4libur · Answer

d=25…25^2=a^2+b^2
area=ab=168

(a+b)^2=a^2+b^2+2ab
(a+b)^2=625+2(168)=961
a+b=√961=31
test a=21, b=31-21=10, ab≠168
test a=24, b=31-24=7, ab=168

Ans (C)

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If the diagonal and the area of a rectangle are 25 units and 168 unit

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If the diagonal and the area of a rectangle are 25 units and 168 unit

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