Basic Geometrical Ideas
Exercise – 4.4
Ex 4.4 Question 1.
1. Draw a rough sketch of a triangle ABC. Mark a point P in its interior and a point Q in its exterior. Is the point A in its exterior or in its interior?
Solution:
Point A is neither interior nor exterior of the triangle. It is a vertex.
Ex 4.4 Question 2.
2. (a) Identify three triangles in the figure.
(b) Write the names of seven angles.
(c) Write the names of six line segments
(d) Which two triangles have ∠B as common?
Solution:
(a) The three triangles = ∠ABD, ∠ACB, ∠ADC
(b) The angles = ∠BAC, ∠BAD, ∠CAD, ∠ADB, ∠ADC, ∠ABC, ∠ACB
(c) The line segments =
,
,
,
,
,
(d) ∠ABD and ∠ABC are triangles that have ∠B as common.