Advertisements
Advertisements
Question
In the given figure, express a in terms of b.

Advertisements
Solution
In Δ ABC,
BC = BA
∴ ∠BCA = ∠BAC
and Ext. ∠CBE = ∠BCA + ∠BAC
⇒ a = ∠BCA + ∠BCA

⇒ a = 2 ∠BCA .........(i)
But ∠ACB = 180° − b ..........(∵ ∠ACD and ∠ACB are linear pair)
⇒ ∠BCA = 180° − b .............(ii)
∴ a = 2 ∠BCA = 2 (180° − b)
= 360°− 2b
APPEARS IN
RELATED QUESTIONS
Is the following statement true and false :
An exterior angle of a triangle is less than either of its interior opposite angles.
If two acute angles of a right triangle are equal, then each acute is equal to
If one angle of a triangle is equal to the sum of the other two angles, then the triangle is
In ΔPQR, If ∠R > ∠Q then ______.
The length of the sides of the triangle is given. Say what types of triangles they are 3.7 cm, 3.4 cm, 4 cm.
The length of the three segments is given for constructing a triangle. Say whether a triangle with these sides can be drawn. Give the reason for your answer.
12 cm, 12 cm, 16 cm
The angles of a triangle are in the ratio 2 : 3 : 4. Then the angles are
One of the angles of a triangle is 65°. If the difference of the other two angles is 45°, then the two angles are
The number of triangles in the following figure is ______. Their names are ______.

Can we have two acute angles whose sum is a right angle? Why or why not?
