Advertisements
Advertisements
Question
In the given figure, if AE || DC and AB = AC, the value of ∠ABD is

Options
70°
110°
120°
130°
Advertisements
Solution
We have to find the value of ∠ABD in the following figure.

It is given that
∠MAE = 70°
∠NAC = 70°(Vertically apposite angle)
Now ∠MAE + ∠EAB + ∠BAC =180° (linear pair) …… (1)
Similarly ∠EAB +∠BAC +∠NAC = 180° (linear pair) …… (2)
From equation (1) we have
∠EAB + ∠BAC = 180°
= 110°
Now ∠FCA = ∠DBA (same exterior angle)
∠ACF = ∠EAC (Interior angle)
Now
∠EAC = 110°
So ∠AFC = 110°
Since ∠AFC =∠ABD
Hence (b)∠ABD = 110°.
APPEARS IN
RELATED QUESTIONS
If ΔDEF ≅ ΔBCA, write the part(s) of ΔBCA that correspond to ∠E
Find the measure of each angle of an equilateral triangle.
If ΔABC ≅ ΔABC is isosceles with
In triangles ABC and PQR, if ∠A = ∠R, ∠B = ∠P and AB = RP, then which one of the following congruence conditions applies:
From the information shown in the figure, state the test assuring the congruence of ΔABC and ΔPQR. Write the remaining congruent parts of the triangles.

State, whether the pairs of triangles given in the following figures are congruent or not:

In ΔPQR, LM = MN, QM = MR and ML and MN are perpendiculars on PQ and PR respectively. Prove that PQ = PR.
Prove that in an isosceles triangle the altitude from the vertex will bisect the base.
In ΔABC, AB = AC. D is a point in the interior of the triangle such that ∠DBC = ∠DCB. Prove that AD bisects ∠BAC of ΔABC.
O is any point in the ΔABC such that the perpendicular drawn from O on AB and AC are equal. Prove that OA is the bisector of ∠BAC.
