Step-by-step explanation:
Well in general, we can represent subtraction as: 
"z" represents the difference, and it really just represents x with y taken away. So if we were to "give back" this y value, we should get "x".
This means that: 
So one way to check, is adding the value that's being subtracted (y value) and the difference (z value), this should get you the value that is being subtracted from (x value). If you don't get the original value that's being subtracted from (x-value) then you know the answer you got is wrong.
Answer:
0.128rad/sec
Step-by-step explanation:
Let x represent the between the man and the point on the path
θ = the angle
dx/dt = 4 ft/s
dθ/dt = rate is the searchlight rotating when the man is 15 ft from the point on the path closest to the searchlight
tan θ = x/20 ft
Cross Multiply
20tan θ = x
dx/dt = 20sec² θ dθ/dt
dθ/dt = 1/20 × cos² θ dx/dt
dθ/dt= 1/20 × cos² θ × 4
dθ/dt = 1/5 × cos² θ
Note : cos θ = 4/5
dθ/dt = 1/5 × (4/5)²
dθ/dt = 16/125
dθ/dt = 0.128rad/sec
Answer: 
Step-by-step explanation:
The area of a rectangle can be calculated with the formula:

l: the length of the rectangle.
w: the width of the rectangle.
The area of the remaning wall after the mural has been painted, will be the difference of the area of the wall and the area of the mural.
Knowing that the dimensions of the wall are
by
, its area is:

As they are planning that the dimensions of the mural be
by
, its area is:

Then the area of the remaining wall after the mural has been painted is:

The "relative frequency" is
(number of times a blue marble came out)
divided by
(total number of trials before everybody got bored and quit) .
-- The relative frequency of blue was (20/60) = (33 and 1/3) % .
(Even though 38.5% of the marbles in the jar are blue,
they didn't get picked that often.)
-- The relative frequency of green was (18/60) = 30 % .
(Even though only 26.9% of the marbles in the jar are green,
they got picked more often than that.)
-- The relative frequency of red was (22/60) = (36 and 2/3) % .
(Even though 42.3% of the marbles in the jar are red,
they didn't get picked that often.)
Answer:
$4.60
Step-by-step explanation:
The customer will pay $0.80 per pound. They are buying 5 and 3/4 pounds of nails, so they will pay..
$0.80(5) + $0.80(3/4) for the nails...now simplify...
$4.00 + $0.60 = $4.60