Answer:
4.1 billion
Step-by-step explanation:
1 ft = 30.48 cm
1 in = 2.54 cm
The volume of rain that fell on the roof is given by ...
V = LWH
V = (175 ft × 30.48 cm/ft)(45 ft × 30.48 cm/ft)(11 in × 2.54 cm/in)
= 175×45×11×30.48²×2.54 cm³ = 204,412,236.336 cm³
At 20 drops per cm³, this will be ...
20×204,412,236.336 ≈ 4,088,244,727 . . . . raindrops
About 4.1 billion raindrops fell on your roof.
Answer:
Below
Step-by-step explanation:
All figures are squares. The area of a square is the side times itself
Let A be the area of the big square and A' the area of the small one in all the 5 exercices
51)
● (a) = A - A'
A = c^2 and A' = d^2
● (a) = c^2 - d^2
We can express this expression as a product.
● (b) = (c-d) (c+d)
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52)
● (a) = A-A'
A = (2x)^2 = 4x^2 and A'= y^2
● (a) = 4x^2 - y^2
● (b) = (2x-y) ( 2x+y)
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53)
● (a) = A-A'
A = x^2 and A' = y^2
● (a) = x^2-y^2
● (b) = (x+y) (x-y)
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54)
● (a) = A-A'
A = (5a)^2 = 25a^2 and A' =(2b)^2= 4b^2
● (a) = 25a^2 - 4b^2
● (a) = (5a-2b) (5a+2b)
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55)
● (a) = A - 4A'
A = (3x)^2 = 9x^2 and A'= (2y)^2 = 4y^2
● (a) = 9x^2 - 4 × 4y^2
● (a) = 9x^2 - 16y^2
● (a) = (3x - 4y) (3x + 4y)
-5x-2y=2....(1)
6x-2y=24.....(2)
multiply (2) by -1,
-6x+2y=-24....(3)
add (1)+(3)
-5x-2y-6x+2y=2-24
-11x=-22
-11x/11=-22/11
x=2
plugging in the value of x in (1)
-5(2)-2y=2
-10-2y=2
addind 10 to both sides
-2y=12
deviding both sides by -2
y=-6
so (x,y)=(2,-6)
Answer:
10ab-5a
Step-by-step explanation:
Just write it backwards.
