Answer:
x greater than or equal to 5
Angle C is 4 square root 11 or in decimals 13.266
We write the equation in terms of dy/dx,
<span>y'(x)=sqrt (2y(x)+18)</span>
dy/dx = sqrt(2y + 18)
dy/dx = sqrt(2) ( sqrt(y + 9))
Separating the variables in the equation, we will have:
<span>1/sqrt(y + 9) dy= sqrt(2) dx </span>
Integrating both sides, we will obtain
<span>2sqrt(y+9) = x(sqrt(2)) + c </span>
<span>where c is a constant and can be determined by using the boundary condition given </span>
<span>y(5)=9 : x = 5, y = 9
</span><span>sqrt(9+9) = 5/sqrt(2) + C </span>
<span>C = sqrt(18) - 5/sqrt(2) = sqrt(2) / 2</span>
Substituting to the original equation,
sqrt(y+9) = x/sqrt(2) + sqrt(2) / 2
<span>sqrt(y+9) = (2x + 2) / 2sqrt(2)
</span>
Squaring both sides, we will obtain,
<span>y + 9 = ((2x+2)^2) / 8</span>
y = ((2x+2)^2) / 8 - 9
we know that
The unit rate is $0.65 per foot
so
To find out the cost, multiply the unit rate by the length of the rope
so
0.65*(10.8)=$7.02
therefore
<h2>The cost is $7.02</h2>
For solving this we need the change in distance and the change in time. You said that the change in time is 1.8 seconds and the change in distance is 3.6 meters. ( This is assuming it started at 0 meters and started at 0 seconds )
Since the starting was 0,0 we can toss them out as they add no value. Now since speed is labeled (in this case) m/s, we divide how many meters it traveled over how many seconds it took to travel it.
3.6 / 1.8 = 2
The average speed of the cart is 2 m/s
