Answers. (1) Parallelogram. Remember: A four-sided flat shape where the opposite sides are parallel is called a parallelogram. Here, AB DC and BC AD.

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1 Answers (1) Parallelogram Remember: A four-sided flat shape where the opposite sides are parallel is called a parallelogram. Here, AB DC and BC AD. (2) straight angle The angle whose measure is 180 will look as: It is called a straight angle.

2 (3) 7 cm It is given that the circumference (P) of the given circle is 1 cm more than thrice its diameter (D), P = 1 + 3D We know, the circumference of circle is πd, where D is the diameter. Therefore, πd = 1 + 3D 22 7 D = 1 + 3D ( )D = D = 1 D = D = 7 cm (4) 50 Since ABC = 90, we can say that a + b = 90. We're also given that a b = 4 5. Cross multiplying the fractions we get 5a = 4b, and on dividing both sides by 5 we get, a = 4b 5. Putting this value of a in a + b = 90, we get 4b 5 + b = 90, or 9 5 b = 90. Cross multiplying the fractions again we get b = , or b = 50. Therefore, the angle b is 50. (5) A plane Any surface that continues in all directions and extends till infinity is called a Plane.

3 (6) Three (triangle is the figure thus generated) A line segment is part of a line bounded by two distinct end points. We know that one or two line segments cannot be used to form a closed figure, as shown below: Three line segments can be used to form a closed figure. For example, a triangle has three line segments and forms a closed figure. Therefore, three is the minimum number of line segments required to form a closed figure.

4 (7) Both angles are 90. The two angles are said to be supplementary if the sum of their measures is 180. When two angles are vertically opposite to each other, they must be equal. Let the two angles in question be a and b. Since, the sum of the two angles is 180, we can write: a + b = 180 or, 2a = 180 (Since, a and b are equal) or, a = 90 Step 5 Since, a = b, the measure of b = 90. Step 6 Therefore, the value of either of the angle is 90. (8) 422.4dm The diameter of a circle is twice the radius of the circle. So, diameter = 2 radius = = dm The question tells us that "pi", the ratio of the circle's circumference to the diameter = 3. This means, Circumference Diameter = 3, or Circumference = 3 Here, we know the divisor and the quotient. The dividend or the circmference = Divisor Quotient = = dm. Step 5 Hence, the circumference of the circle is dm

5 (9) isosceles triangle A triangle having two sides of equal length is called an isosceles triangle. Let us understand this through the following illustration: In the figure above, ABC is a triangle in which AB BC = CA. Hence, a triangle whose two out of three sides are equal is called an isosceles triangle. (10) acute angle The angle whose measure is more than 0 and less than 90 will look as: It is called an acute angle.

6 (11) Parallel lines If two lines are drawn in a plane such that they never intersect and extend indefinitely in both the directions maintaining an equal distance, they are called parallel lines. Let us look at the figure below: In the above figure, lines 'a' and 'b' are parallel. We can represent this fact as: a b. (12) 30 We know that the sum of all the interior angles of a triangle is 180. Therefore, for triangle ΔABC, CBD + BCA + CAD = 180 CBD = 180 CBD = ( ) CBD = 60 Similarly, for the triangle ΔCDB, CBD + DCB + CDB = DCB + 90 = 180 DCB = ( ) DCB = 30

7 (13) b. collinear Let us draw the points that lie on a straight line. P Q R P, Q, and R are collinear points. The points which lie on a straight line are called collinear points. (14) a. All rectangles are regular polygons Let us go by the options. Option a: A regular polygon is one which all the angles and all the sides are equal. But a rectangle has only the opposite pair of sides equal. Adjacent sides of a rectangle may or may not be equal. Hence, the statement is incorrect. Option b: A square is a special type of quadrilateral. Hence, the statement is correct. Option c: A rectangle is a special type of quadrilateral, so all rectangles are quadrilaterals. Hence, the statement is correct. Step 5 Option d: A square has four equal sides and its opposite sides are parallel to each other. The opposite sides of a rectangle are parallel and equal to each other. A square can, thus, be a special case of a rectangle. Hence, the statement is correct. Step 6 Hence, option a is incorrect.

8 (15) True Let us first recall the fact that the sum of all three angles of a triangle is 180 degrees. Let us now look at the definition of supplementary angles: two angles are called supplementary if the sum of their measures is 180 degrees. We need to find if we can have a triangle which has a pair of supplementary angles. For a moment, let us assume that such a triangle exists. In such a triangle, the sum of two angles (supplementary ones) will be 180 degrees. This means that the third angle needs to measure zero degree. We know that we cannot create a triangle with one of the angles measuring zero degrees. Step 5 This means, it is not possible for an angle and its supplementary angle to be part of a triangle.

Grade 5 Geometry. Answer the questions. For more such worksheets visit

Grade 5 Geometry. Answer the questions. For more such worksheets visit ID : ae-5-geometry [1] Grade 5 Geometry For more such worksheets visit www.edugain.com Answer the questions (1) A 4-sided flat shape with straight sides where the opposite sides are parallel is called