Quadrilaterals: Angle and Parallelogram
Assignments in Mathematics Class IX (Term 2) 8. QUADRILATERALS
IMPORTANT TERMS, DEFINITIONS AND RESULTS l l
Sum of the angles of a quadrilateral is 360°. A diagonal of a parallelogram divides it into two congruent triangles. In a parallelogram, (i) opposite sides are equal (ii) opposite angles are equal (iii) diagonals bisect each other A quadrilateral is a parallelogram, if (i) opposite sides are equal or (ii) opposite angles are equal or (iii) diagonals bisect each other or (iv) a pair of opposite sides is equal and parallel
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Diagonals of a rectangle bisect each other and are equal and vice-versa. Diagonals of a rhombus bisect each other at right angles and vice-versa. Diagonals of a square bisect each other at right angles and are equal, and vice-versa. The line segment joining the mid-points of any two sides of a triangle is parallel to the third side and is half of it. A line through the mid-point of a side of a triangle parallel to another side bisects the third side. The quadrilateral formed by joining the mid-points of the sides of a quadrilateral, in order, is a parallelogram.
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SUMMATIVE ASSESSMENT MULTIPLE CHOICE QUESTIONS
PR AK AS HA N
(a) 90° (b) 180°
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[1 Mark]
A. Important Questions
1. Two consecutive angles of a parallelogram are in the ratio 1 : 3. Then the smaller angle is : (a) 50° (b) 90° (c) 60° (d) 45° 2. A quadrilateral is a parallelograms if : (a) both pairs of opposite sides are equal (b) both pairs of opposite angles are equal (c) the diagonals bisect each other (d) all of these 3. ABCD is a rhombus. Diagonal AC is equal to one of its sides. Then ∆ABC must be : (a) a right angled triangle (b) an equilateral triangle (c) an isosceles triangle (d) none of these 4. In the figure, ABCD is a parallelogram. The values of x and y are respectively :
BR O TH ER S
G O YA L
(a) 80° (b) 90° (c) 50° (d) 100° 6. The sum of three angles of a quadrilateral is 3 right angles. Then the fourth
IMPORTANT TERMS, DEFINITIONS AND RESULTS l l
Sum of the angles of a quadrilateral is 360°. A diagonal of a parallelogram divides it into two congruent triangles. In a parallelogram, (i) opposite sides are equal (ii) opposite angles are equal (iii) diagonals bisect each other A quadrilateral is a parallelogram, if (i) opposite sides are equal or (ii) opposite angles are equal or (iii) diagonals bisect each other or (iv) a pair of opposite sides is equal and parallel
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Diagonals of a rectangle bisect each other and are equal and vice-versa. Diagonals of a rhombus bisect each other at right angles and vice-versa. Diagonals of a square bisect each other at right angles and are equal, and vice-versa. The line segment joining the mid-points of any two sides of a triangle is parallel to the third side and is half of it. A line through the mid-point of a side of a triangle parallel to another side bisects the third side. The quadrilateral formed by joining the mid-points of the sides of a quadrilateral, in order, is a parallelogram.
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SUMMATIVE ASSESSMENT MULTIPLE CHOICE QUESTIONS
PR AK AS HA N
(a) 90° (b) 180°
l
[1 Mark]
A. Important Questions
1. Two consecutive angles of a parallelogram are in the ratio 1 : 3. Then the smaller angle is : (a) 50° (b) 90° (c) 60° (d) 45° 2. A quadrilateral is a parallelograms if : (a) both pairs of opposite sides are equal (b) both pairs of opposite angles are equal (c) the diagonals bisect each other (d) all of these 3. ABCD is a rhombus. Diagonal AC is equal to one of its sides. Then ∆ABC must be : (a) a right angled triangle (b) an equilateral triangle (c) an isosceles triangle (d) none of these 4. In the figure, ABCD is a parallelogram. The values of x and y are respectively :
BR O TH ER S
G O YA L
(a) 80° (b) 90° (c) 50° (d) 100° 6. The sum of three angles of a quadrilateral is 3 right angles. Then the fourth