Advertisements
Advertisements
Question
Show that in a right angled triangle, the hypotenuse is the longest side.
Advertisements
Solution

Let us consider a right-angled triangle ABC, right-angled at B.
In ΔABC,
∠A + ∠B + ∠C = 180° ...(Angle sum property of a triangle)
∠A + 90º + ∠C = 180°
∠A + ∠C = 90°
Hence, the other two angles have to be acute i.e., less than 90º.
∴ ∠B is the largest angle in ΔABC.
⇒ ∠B > ∠A and ∠B > ∠C
⇒ AC > BC and AC > AB
In any triangle, the side opposite to the larger (greater) angle is longer.
Therefore, AC is the largest side in ΔABC.
However, AC is the hypotenuse of ΔABC.
Therefore, hypotenuse is the longest side in a right-angled triangle.
APPEARS IN
RELATED QUESTIONS
In the given figure, ∠B < ∠A and ∠C < ∠D. Show that AD < BC.

AB and CD are respectively the smallest and longest sides of a quadrilateral ABCD (see the given figure). Show that ∠A > ∠C and ∠B > ∠D.

In the given figure, PR > PQ and PS bisects ∠QPR. Prove that ∠PSR >∠PSQ.

Show that of all line segments drawn from a given point not on it, the perpendicular line segment is the shortest.
In a huge park people are concentrated at three points (see the given figure):

A: where there are different slides and swings for children,
B: near which a man-made lake is situated,
C: which is near to a large parking and exit.
Where should an ice-cream parlour be set up so that maximum number of persons can approach it?
(Hint: The parlor should be equidistant from A, B and C)
In a triangle PQR; QR = PR and ∠P = 36o. Which is the largest side of the triangle?
In the following figure, write BC, AC, and CD in ascending order of their lengths.
Arrange the sides of ∆BOC in descending order of their lengths. BO and CO are bisectors of angles ABC and ACB respectively.

Name the greatest and the smallest sides in the following triangles:
ΔXYZ, ∠X = 76°, ∠Y = 84°.
Name the smallest angle in each of these triangles:
In ΔABC, AB = 6.2cm, BC = 5.6cm and AC = 4.2cm
Name the smallest angle in each of these triangles:
In ΔPQR, PQ = 8.3cm, QR = 5.4cm and PR = 7.2cm
In a triangle ABC, BC = AC and ∠ A = 35°. Which is the smallest side of the triangle?
In ΔABC, the exterior ∠PBC > exterior ∠QCB. Prove that AB > AC.
Prove that the perimeter of a triangle is greater than the sum of its three medians.
D is a point on the side of the BC of ΔABC. Prove that the perimeter of ΔABC is greater than twice of AD.
In ΔPQR, PR > PQ and T is a point on PR such that PT = PQ. Prove that QR > TR.
ABCD is a trapezium. Prove that:
CD + DA + AB > BC.
Prove that in an isosceles triangle any of its equal sides is greater than the straight line joining the vertex to any point on the base of the triangle.
In ΔABC, AE is the bisector of ∠BAC. D is a point on AC such that AB = AD. Prove that BE = DE and ∠ABD > ∠C.
