Page 313 - Math Smart - 7

Using a protractor, draw a line that is Draw the line CB to complete
5 perpendicular to line AB from point A. 4" triangle ABC. Draw a square to
Label the point at which the line cuts show that aCAB is a right angle.
the arc C.

4 cm

5 cm
5 cm
Constructing isosceles triangles

Construct a triangle ABC such that AS = 5 cm, and LABC = /.CAB = 40".
Draw a sketch to help you.
Solution C
A B
Draw a line AB = S cm. 5 cm
1

5 cm
Using a protractor, construct /. = 40".

Using the protractor, construct A = 40°. Label the point at which the two lines meet C.

5 cm
5 cm
Observe that we can construct a triangle
• if we are given the lengths of two sides and the if we are given the sizes of two angles and
size of the angle between the two given sides. the length of the side between the two given
This is known as side-angle-side or SAS. angles. This is known as angle-side-angle or ASA.

side

side