Drawing Triangles using Geometrical Instruments - Part 2

1. Draw an isosceles triangle PQR in which PQ = PR, QR = 6 cm and ∠PQR = 50°.


Step 1: Draw a straight line QR 6 cm long.

drawing an isosceles triangle
Step 2: Using a protractor draw an angle of 50° from Point Q.

drawing an isosceles triangle
Step 3: Using a protractor draw an angle of 50° from Point R.

drawing an isosceles triangle
The angles opposite the equal sides in an isosceles triangle are equal.
Therefore, ∠PQR = ∠PRQ = 50°.
Step 4: Mark the point where the two lines meet as P.

drawing an isosceles triangle
ΔPQR is the required isosceles triangle.

2. Draw a right-angled triangle XYZ with ∠XYZ = 90°, YZ = 5 cm and XY = 4 cm.


Step 1: Draw a straight line YZ 5cm long.

drawing a right-angled triangle
Step 2: Using a protractor draw a right angle (an angle of 90°) from Point Y.

drawing a right-angled triangle
Step 3: Mark the point X so that XY = 4 cm. Then, join Point X and Point Z.

drawing a right-angled triangle
Δ XYZ is the required right-angled triangle.