Answer:
2
Step-by-step explanation:
Perimeter of a rectangle = 2(length + breadth)
=> 2{2x + (x + 4)) = 20
=> (2x + x + 4) = 20/2 = 10
=> 3x + 4 = 10
=> 3x = 10 - 4 = 6
=> x = 6/3 = 2
Here, according to the diagram
Length = 2x = 2(2) = 4
Breadth = x + 4 = 2+4 = 6
But breadth should always be lesser than the length. From this, it can be concluded that the actual breadth is 2x and actual length is x + 4, for perimeter to be 20.
Answer:
e.869.58units^2
f. 96m^2
g. 184m^2
Step-by-step explanation:
e.
484 square
176 triangle
209.58 equilateral triangle
f. 196 total are - mini square 25+25+25+25= 96m^2
g. 22+66+80+16=184m^2
Answer:
x = 10 cm, y = 5 cm gives a minimum area of 300 cm^2.
Step-by-step explanation:
V= x^2y = 500
Surface area A = x^2 + 4xy.
From the first equation y = 500/x^2
So substituting for y in the equation for the surface area:
A = x^2 + 4x * 500/x^2
A = x^2 + 2000/x
Finding the derivative:
dA/dx = 2x - 2000x^-2
dA/dx = 2x - 2000/x^2
This = 0 for a minimum/maximum value of A, so
2x - 2000/x^2 = 0
2x^3 - 2000 = 0
x^3 = 2000/ 2 = 1000
x = 10
Second derivative is 2 + 4000/x^3
when x = 10 this is positive so x = 10 gives a minimum value of A.
So y = 500/x^2
= 500/100
= 5.
Answer:
...
Step-by-step explanation:
<span>A number is divisible by 9, if the sum is a multiple of 9 or if the sum of its digits is divisible by 9.
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