Answer:
They will meet after four hours
Step-by-step explanation:
The boat moving at 2.5 mph will have travelled 10 miles after 4 hrs, and the boat moving at 5 mph will have travelled 20 miles after 4 hrs
Y varies inversely with x
means that y=k/x
with x=0.7 and y=80
we have 80=k/0.7
k=0.7x80=56
so the equation is
y=56/x
Answer:
Height: 3/2 inches
Length: 12 inches
Width: 4 inches
Step-by-step explanation:
Let x is the side length of the square
The height of the box by cutting squares off :x
- The new length of the cardboard = 15 -2x (because we cut from 4 corners)
- The new width of the cardboard = 7 -2x (because we cut from 4 corners)
The new volume of it is:
V = (15 -2x) (7 -2x) x
<=> V =
To maximum volume, we use the first derivative of the volume
<=> 
<=> 
<=> 2x -3 = 0 or 6x -35 = 0
<=> x = 3/2 or x = 35/6
To determine which value of x gives a maximum, we evaluate
= 24x -88
= 24(3/2) -88 = -52
= 24(35/6) -88 = 52
We choose x = 3/2 to have the maximum volume because the value of x that gives a negative value is maximum.
So the dimensions (in inches) of the box is:
Height: 3/2 inches
Length: 15-2(3/2) = 12 inches
Width: 7 - 2(3/2) = 4 inches
9,6^2+18,8^2=X^2
92,16+353,44=X^2
X^2=445,6
X=21
Answer:
x = 0
Step-by-step explanation:

Expanding the left hand side we get

Taking 6 from left hand side to right hand side

Dividing both sides by 2

So, x = 0