Request a call back

hi
Asked by chaudahryanshika | 03 Jan, 2023, 10:04: AM
Question (5)

Quadratic equation :- a x2 + b x + c = 0

for real roots , b2 = ( 4 a c  )

Given quadratic equation :- x2 + 4x + k= 0

a =1 , b = 4 , c = 1

b2 = 16

4 ac = 4 k = 16

Hence k = 4
-----------------------------------------------------------------------

Question (6)

As shown in figure , we gwt the sides of triangle as 4 unit, 3 unit and 5 unit.

Hence perimeter = 12 unit

-----------------------------------------------------------------------------------------

Question (7)

In a given similar triangles ABC and DEF

----------------------------------------------------------------------------

Question (8) Partially hidden, unable to answer

-------------------------------------------

Question (9)

because
ΔOAB is isoceless because OA = OB

Hence
---------------------------------------------------------

Question (10)
------------------------------------------------

Question (11)

-----------------------------------------------------
Question (12)

cos1o cos2o cos3o ..........................cos88o cos89o cos90o = 0

because cos90 = 0 and ita ppears in product

-----------------------------------------------------

Question (13)

let r be the radius of circle. perimeter is ( 2r )

If perimeter of square is ( 2r ) then side of square ( 2r )/4 = ( r )/2

Area of circle : area of square = r2  : (1/4) 2 r2

Let us use = 22/7 , then if simplify above ratio , we get areas are in the ratio 14 : 11

-------------------------------------------------------

Question (14)

area of circle is proportioanl to square of radius.

If radii of circle are in the ratio 4:3 , then areas are in the ratio 16:9

---------------------------------------------

Question (15)

Total surface area of solid hemisphere = 3r2 = 3×49 = 147 cm2

-------------------------------------

Question 16

Modal class is between 15 to 20 , because frequency is highest for this class.

Upper limit is 20
Answered by Thiyagarajan K | 03 Jan, 2023, 02:26: PM

## Concept Videos

CBSE 10 - Maths
Asked by ruchipandey20071978 | 21 May, 2023, 10:00: PM
CBSE 10 - Maths
Asked by varma.renu9481 | 25 Jan, 2023, 04:11: PM
CBSE 10 - Maths
Asked by chaudahryanshika | 03 Jan, 2023, 10:04: AM
CBSE 10 - Maths
Asked by devchauhan25007 | 17 Jul, 2022, 04:29: PM
CBSE 10 - Maths
Asked by sdiyashika | 12 Apr, 2022, 03:07: PM
CBSE 10 - Maths
Asked by hazelvermah | 19 Apr, 2021, 09:02: AM