SHORT ANSWER TYPE QUESTIONS :-
31. Write the additive inverse of 19/-6.
32. Mention the rational number that has no reciprocal.
33. Define a rational number.
34. Solve 7x – 12 = 16.
35. Solve 3 (x - 4) = 21
36. What is the sum of all interior angles of a quadrilateral ?
37. Name the quadrilateral that has one pair of parallel sides.
38. Name the parallelogram in which one of its angle is 90˚.
39. How many diagonals does a regular hexagon has?
40. angle A and angle B are two adjacent angles of a parallelogram. If angle A = 70˚, then what is the measure Of angle B?
Answers
Explanation:
31.
Given number = 19/-6 = -19/6
The additive inverse of 19/-6 = 19/6
32 .
The rational number that has no reciprocal is 0
Because The division by zero is not defined and meaningless
33.
A rational number:
The number can be written as p/q , where p and q are integers and q ≠ 0 is called a rational number.
Ex:- 2/3 , -1/7 ...
34.
Given equation is 7x – 12 = 16.
=> 7x = 16+12
=> 7x = 28
=> x = 28/7
=> x = 4
The solution is 4
35.
Given equation is 3 (x - 4) = 21
=> x-4 = 21/3
=> x-4 = 7
=> x = 7+4
=> x = 11
The Solution is 11
36.
The sum of all interior angles of a quadrilateral is 360° or 4 right angles.
37.
If one pair of opposite sides are parallel in a quadrilateral then it is called Trapezium.
38.
We know that Opposite angles are equal and adjacent angles are supplementary
If one angle is 90° then all the angles are 90°,90°, 90° and 90°
So it is a rectangle
39.
We know that
If n is the number of sides in a regular polygon then the no.of diagonals is n(n-3)/2
Given that a regular hexagon
Number of sides in the hexagon = 6
n = 6
Number of diagonals = 6(6-3)/2
=> 6(3)/2
=> 3×3
=> 9
The number of diagonals in the regular hexagon is 9
40.
Given that
angle A and angle B are two adjacent angles of a parallelogram.
angle A = 70°
We know that
adjacent angles are supplementary in a Parallelogram
angle A + angle B = 180°
=> 70°+angle B = 180°
=> angle B = 180°-70°
=> angle B = 110°
The measure of angle B = 110°