Advertisements
Advertisements
Question
If the angles A, B and C of ΔABC satisfy the relation B − A = C − B, then find the measure of ∠B.
Advertisements
Solution
In the given ΔABC,
∠A, ∠B and ∠C satisfy the relation B - A = C - B
We need to fine the measure of ∠B.

As,
B - A = C - B
B + B = C + A
2B = C + A
2B - A = C ........(1)
Now, using the angle sum property of the triangle, we get,
A + B + C = 180°
2B - A + A +B = 180° (Using 1)
3B = 180°
`B = (180°) / 3`
= 60°
Therefore, ∠B = 60°
APPEARS IN
RELATED QUESTIONS
Determine the measure of each of the equal angles of a right-angled isosceles triangle.
If the base of an isosceles triangle is produced on both sides, prove that the exterior angles so formed are equal to each other.
BD and CE are bisectors of ∠B and ∠C of an isosceles ΔABC with AB = AC. Prove that BD = CE.
Angles A, B, C of a triangle ABC are equal to each other. Prove that ΔABC is equilateral.
ABC is a triangle and D is the mid-point of BC. The perpendiculars from D to AB and AC are equal. Prove that the triangle is isosceles.
Which of the following statements are true (T) and which are false (F) :
If the altitude from one vertex of a triangle bisects the opposite side, then the triangle may be isosceles.
Fill the blank in the following so that the following statement is true.
In an equilateral triangle all angles are .....
In a ΔABC, if ∠B = ∠C = 45°, which is the longest side?
Which of the following statements are true (T) and which are false (F)?
Sum of the three sides of a triangle is less than the sum of its three altitudes.
Fill in the blank to make the following statement true.
Difference of any two sides of a triangle is........ than the third side.
Write the sum of the angles of an obtuse triangle.
In a triangle ABC, if AB = AC and AB is produced to D such that BD = BC, find ∠ACD: ∠ADC.
In the given figure, if EC || AB, ∠ECD = 70° and ∠BDO = 20°, then ∠OBD is
In the given figure, x + y =

In the given figure, if AB ⊥ BC. then x =

In the given figure, what is y in terms of x?

If ∆PQR ≅ ∆EDF, then is it true to say that PR = EF? Give reason for your answer
Find all the angles of an equilateral triangle.
Show that in a quadrilateral ABCD, AB + BC + CD + DA > AC + BD
