2.
opposite angles
the angles of the triangle.
The three angles of a triangle are in the ratio 2:1:2. Find the measure of the angles and state the kind of triangle
3.
ndithe following can be the measure of the sofa triangle Give reasons.
Answers
Correct Question:
The three angles of a triangle are in the ratio 2:1:2. Find the measure of each angle and state what type of triangle it is.
Answer:
Angle measures = 72°, 36°, 72°
Type of triangle = Acute angled triangle
Solution:
Let the three angles of the triangle be 2x, 1x and 2x. ------ (1)
We know that the sum of all the angles of a triangle is 180°. ------ (2)
Combining statements (1) and (2):
2x + 1x + 2x = 180°
5x = 180°
x = 180/5
x = 36
So,
2x = 2 x 36 = 72°
1x = 1 x 36 = 36°
2x = 2 x 36 = 72°
Hence the three angles of the triangle are 72°, 36° and 72°.
As all the angles are below 90°, it is an acute angled triangle.
Knowledge Bytes:
→ Classification of triangles on basis of angles:
✳ Acute angled triangle
A triangle that has all the measures below 90° is known as an acute angled triangle.
✳ Right angled triangle
A triangle that has one angle equal to 90° is known as a right angled triangle.
✳ Obtuse angled triangle
A triangle that has one angle more than 90° is known as obtuse angled triangle.
→ Angle Sum Property of Triangles
The sum of all the angles of a triangle is 180°.