A closed figure formed by three intersecting lines is called

1

(a)

circle

(b)

square

(c)

triangle

(d)

rhombus

'Tri' means

1

(a)

one

(b)

two

(c)

three

(d)

four

Two circles are congruent.If the radius of one circle is 3cm, what is the radius of the other circle?

1

(a)

3 cm

(b)

6 cm

(c)

1.5 cm

(d)

1 cm

Two circles are congruent.If the radius of one circle is 1cm, then the diameter of the other circle is

1

(a)

1 cm

(b)

2 cm

(c)

4 cm

(d)

0.5 cm

Two circles are congruent.If the diameter of one circle is 2cm, then the radius of the other circle is

1

(a)

1 cm

(b)

2 cm

(c)

3 cm

(d)

4 cm

Write ASA congruence rule for two triangles.

1

(a)

ASA congruence: Two triangles are congruent, if two angles and the included side of one triangle are equal to two angles and the included side of other triangle.

In \(\triangle\)ABC and \(\triangle\)DEF, AB=DE, \(\angle\)A=\(\angle\)D. What will be the condition in which the two triangles will be congruent by SAS axiom?

1

(a)

Since AB = DE, \(\angle\)A =\(\angle\)D and \(\triangle\)ABC\(\cong \)\(\triangle\)DEF by SAS.
Therefore AC = DF.

What do we call a triangle if the angles are in the ratio 5 : 3 : 7?

1

(a)

Let the angles of triangle are 5x, 3x and 7x, then
5x + 3x + 7x = 180°
\(\Rightarrow\) 15x = 180°
Thus, x = 12°
\(\therefore\) Angles are 60°, 36°, 84°
\(\therefore\) Each angle is less than 90°
\(\therefore\) The triangle is an acute-angled triangle.

In given fig., AD = BC and \(\angle\)BAD =\(\angle\)ABC, then prove that \(\angle\)ACB = \(\angle\)BDA.

1

(a)

AD = BC  (Given)
\(\angle\)BAD =\(\angle\)ABC  (Given)
AB = AB   (Common)
\(​​\triangle DAB\cong \triangle CBA\) (By SAS)
\(\angle\)BDA =\(\angle\)ACB    (By c.p.ct)

\(\triangle PQR\cong \triangle ABC\), if PQ = 5 cm, \(\angle\)Q = 40° and \(\angle\)P = 80°, calculate the value of \(\angle\)C.

1

(a)

\(\angle\)R= 180° - 80° - 40° = 60°
\(\triangle PQR\cong \triangle ABC\)
\(\therefore\) \(\angle\)R = \(\angle\)C = 60°