Advertisements
Advertisements
Question
Find the perimeter of the rectangle whose length is 40 cm and a diagonal is 41 cm.
Advertisements
Solution
Length of rectangle = 40 cm, Diagonal = 41 cm
Let the breadth of rectangle = x cm

From right angled triangle ΔABC,
AC2 = AB2 + BC2
(41)2 = (40)2 + BC2
BC2 = 1681 – 1600
BC2 = 81
BC = 9
Perimeter of rectangle = 2 (40 + 9)
= 2 × 49
= 98 cm
Hence, perimeter of rectangle = 98 cm
APPEARS IN
RELATED QUESTIONS
In figure, ∠B of ∆ABC is an acute angle and AD ⊥ BC, prove that AC2 = AB2 + BC2 – 2BC × BD
Prove that the points A(0, −1), B(−2, 3), C(6, 7) and D(8, 3) are the vertices of a rectangle ABCD?
Some question and their alternative answer are given. Select the correct alternative.
If a, b, and c are sides of a triangle and a2 + b2 = c2, name the type of triangle.
In ∆ABC, seg AD ⊥ seg BC, DB = 3CD.
Prove that: 2AB2 = 2AC2 + BC2


In ΔMNP, ∠MNP = 90˚, seg NQ ⊥ seg MP, MQ = 9, QP = 4, find NQ.
In the given figure, AB//CD, AB = 7 cm, BD = 25 cm and CD = 17 cm;
find the length of side BC.
In ∆ ABC, AD ⊥ BC.
Prove that AC2 = AB2 +BC2 − 2BC x BD
In the given figure, angle ACP = ∠BDP = 90°, AC = 12 m, BD = 9 m and PA= PB = 15 m. Find:
(i) CP
(ii) PD
(iii) CD

In ΔABC, if DE || BC, AD = x, DB = x – 2, AE = x + 2 and EC = x – 1, then value of x is ______.
Two squares are congruent, if they have same ______.
