Advertisements
Advertisements
प्रश्न
If one angle of a triangle is equal to the sum of the other two, show that the triangle is a
right triangle.
Advertisements
उत्तर
If one angle of a triangle is equal to the sum of other two
i.e, `∠ B=∠ A+∠C`
Now, in ΔABC
(Sum of all aangles of triangle `180^@`)
`∠ A+∠B+∠ C=180^@`
`∠ B+∠ B=180^@` [∵ ∠ B=∠ A+∠ C]
`2∠ B=180^@`
`∠ B=180^@/2`
`∠ B=90^@`
∴ABC is a right angled a triangle
APPEARS IN
संबंधित प्रश्न
If the bisectors of the base angles of a triangle enclose an angle of 135°, prove that the triangle is a right triangle.
Is the following statement true and false :
An exterior angle of a triangle is greater than the opposite interior angles.
In a Δ ABC, AD bisects ∠A and ∠C > ∠B. Prove that ∠ADB > ∠ADC.
State exterior angle theorem.
In the given figure, side BC of ΔABC is produced to point D such that bisectors of ∠ABC and ∠ACD meet at a point E. If ∠BAC = 68°, find ∠BEC.

Mark the correct alternative in each of the following:
If all the three angles of a triangle are equal, then each one of them is equal to
In a triangle PQR, ∠P = 60° and ∠Q = ∠R, find ∠R.
Can a triangle together have the following angles?
55°, 55° and 80°
In the following figure, AD is the bisector of ∠BAC. Prove that AB > BD.

What is the sum of the measures of the interior angles of any triangle, △ABC?
