Advertisements
Advertisements
Question
If length of both diagonals of rhombus are 60 and 80, then what is the length of side?
Options
100
50
200
400
Advertisements
Solution
50
Explanation:

Let ABCD be the rhombus, diagonal AC = 60 and BD = 80.
We know that the diagonals of a rhombus are perpendicular bisectors of each other.
∴ Diagonals AC and BD bisect each other at point M.
∴ In ∆AMD, ∠M = 90°, AM = 30, DM = 40
∴ AM2 + DM2 = AD2 ...[Pythagoras theorem]
∴ (30)2 + (40)2 = AD2
∴ 900 + 1600 = AD2
∴ AD2 = 2500
∴ AD = 50 units
APPEARS IN
RELATED QUESTIONS
In ∆PQR, PQ = √8 , QR = √5 , PR = √3. Is ∆PQR a right-angled triangle? If yes, which angle is of 90°?
In the rectangle WXYZ, XY + YZ = 17 cm, and XZ + YW = 26 cm. Calculate the length and breadth of the rectangle?

5 m long ladder is placed leaning towards a vertical wall such that it reaches the wall at a point 4 m high. If the foot of the ladder is moved 1.6 m towards the wall, then find the distance by which the top of the ladder would slide upwards on the wall.
In the adjacent figure, ABC is a right angled triangle with right angle at B and points D, E trisect BC. Prove that 8AE2 = 3AC2 + 5AD2

If in ∆ABC, DE || BC. AB = 3.6 cm, AC = 2.4 cm and AD = 2.1 cm then the length of AE is
Two poles of heights 6 m and 11 m stand vertically on a plane ground. If the distance between their feet is 12 m, what is the distance between their tops?
If the sides of a triangle are in the ratio 5 : 12 : 13 then, it is ________
8, 15, 17 is a Pythagorean triplet
The incentre is equidistant from all the vertices of a triangle
Check whether given sides are the sides of right-angled triangles, using Pythagoras theorem
8, 15, 17
Check whether given sides are the sides of right-angled triangles, using Pythagoras theorem
9, 40, 41
Check whether given sides are the sides of right-angled triangles, using Pythagoras theorem
24, 45, 51
The area of a rectangle of length 21 cm and diagonal 29 cm is __________
A rectangle having dimensions 35 m × 12 m, then what is the length of its diagonal?
In ∆LMN, l = 5, m = 13, n = 12 then complete the activity to show that whether the given triangle is right angled triangle or not.
*(l, m, n are opposite sides of ∠L, ∠M, ∠N respectively)
Activity: In ∆LMN, l = 5, m = 13, n = `square`
∴ l2 = `square`, m2 = 169, n2 = 144.
∴ l2 + n2 = 25 + 144 = `square`
∴ `square` + l2 = m2
∴ By Converse of Pythagoras theorem, ∆LMN is right angled triangle.
In ΔABC, AB = 9 cm, BC = 40 cm, AC = 41 cm. State whether ΔABC is a right-angled triangle or not. Write reason.
In the given figure, triangle PQR is right-angled at Q. S is the mid-point of side QR. Prove that QR2 = 4(PS2 – PQ2).

