A) -3 · x = -21 b) -7x + 16 = 2x - 20
2 answers:
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Amount of Interest=7152-6400=752=I
- Principal=6400=P
- Rate of interest=6%=R
- Time=T=?
We know
Answer:
Option (B) is correct .
The constant of proportionality is 7.5 .
Reason
Let us assume that the number of books be x.
Let us assume that the cost of books be y .
Than
y = kx
Where k is constant of proportionality .
As given
Number of Books 4 6 8
Cost ($) 30 45 60
Thus
when x = 4 , y = 30
Put in the equation y = kx .
k = 7.5
when x = 6 , y = 45
Put in the equation y = kx .
k = 7.5
when x = 8 , y = 60
Put in the equation y = kx .
k = 7.5
Therefore the constant of proportionality is 7.5 i.e option (B) is correct .
You have a square with half circles along the sides.
The length of each side is 4ft, so the radius of the circles is 2ft
to calculate the perimeter you can calculate the circumference of 4 half circles = 2 complete circles
c=2r*
=
2*2=12.56
perimeter=2c=25.12=8
the area is the area of 2 circles+the area of the square
circle area= r^2*=2*2=4
concrete area=circle area*2+square area
=4 *2+(4*4)
=8+(4*4)
=8+16ft
=41.12 ft^2
The length of each side is 4ft, so the radius of the circles is 2ft
to calculate the perimeter you can calculate the circumference of 4 half circles = 2 complete circles
c=2r*
2*2
perimeter=2c=25.12=8
the area is the area of 2 circles+the area of the square
circle area= r^2*
concrete area=circle area*2+square area
=4
=8
=8
=41.12 ft^2