Advertisements
Advertisements
Question
An exterior angle of a triangle is equal to 100° and two interior opposite angles are equal. Each of these angles is equal to
Options
75°
80°
80°
40°
50°
Advertisements
Solution
n the ΔABC, CD is the ray extended from the vertex C of ΔABC. It is given that the exterior angle of the triangle is 100° and two of the interior opposite angles are equal.
So, ∠ACD = 100° and A = ∠B

So, now using the property, “an exterior angle of the triangle is equal to the sum of the two opposite interior angles”, we get.
In ΔABC
∠A + ∠B = ∠ACD
∠2A = 100°
`∠A = (100°)/2`
∠A = 50°
∠A = ∠B = 50°
Therefore, each of the two opposite interior angles is 50°.
APPEARS IN
RELATED QUESTIONS
If the angles of a triangle are in the ratio 1: 2 : 3, determine three angles.
The angles of a triangle are arranged in ascending order of magnitude. If the difference
between two consecutive angles is 10°, find the three angles.
Fill in the blank to make the following statement true:
A triangles cannot have more than ......obtuse angles.
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
An exterior angle of a triangle is 108° and its interior opposite angles are in the ratio 4 : 5. The angles of the triangle are
In the given figure, express a in terms of b.

The length of the sides of the triangle is given. Say what types of triangles they are 3 cm, 4 cm, 5 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.
17 cm, 7 cm, 8 cm
D is any point on side AC of a ∆ABC with AB = AC. Show that CD < BD.
Can we have two acute angles whose sum is a straight angle? Why or why not?
