Question

Construct the following angles using set-squares:

(i) 45°
(ii) 90°
(iii) 60°
(iv) 105°
(v) 75°
(vi) 150°

Answer 1

(i) Place 45° set-square.
Draw two rays AB and AC along the edges from the vertex of 45° angle of the set-square.
The angle so formed is a 45° angle.
∠BAC = 45°


(ii) Place 45° set-square as shown in the figure.
Draw two rays BC and BA along the edge from the vertex of 90° angle.
The angle so formed is 90° angle.
∠ABC = 90°



(iii) Place 30° set-square as shown in the figure.
Draw the rays BA and BC along the edges from the vertex of 60°.
The angle so formed is 60°.
∠ABC = 60°



(iv) Place 30° set-square and make an angle of 60° by drawing the rays BA and BC as shown in the figure.


Now, place the vertex of 45° of the set-square on the ray BA as shown in the figure and draw the ray BD.
The angle so formed is 105°
∴ ∠DBC = 105°

(v) Place 45° set-square and make an angle of 45° by drawing the rays BD and BC as shown in the figure.


Now, place the vertex of 30° of the set-square on the ray BD as shown in the figure and draw the ray BA.
The angle so formed is 75°.
∴ ∠ABC = 75°

(Line BD is hidden)

(vi) Place the vertex of 45° of the set-square and make angle of 90° by drawing the rays BD and BC as shown in the figure.

Now, place the vertex of 30° of the set square on the ray BD as shown in the figure and draw the ray BA.
The angle so formed is 150°.
∴ ∠ABC = 150°