John wanted to go on a train. the equation y=9/5 x describes the number of miles y that a train travels in x minutes. what is the constant speed of the train in terms of hours?

The constant speed of the train is 108 miles per hour

4 0

4 years ago

Helppppppp tutorssssss arent workinggg

sashaice [31]

The surface area would be 166.

4 0

3 years ago

Limit as x approaches 9 of x^2 -81/sqrt of x - 3

Ipatiy [6.2K]

Answer:

108

Step-by-step explanation:

Limit as x approaches 9 of x^2 -81/sqrt of x - 3

First substitute x into the expression

= 9²-81/√9 - 3

= 81-81/3-3

= 0/0 (indeterminate)

Apply l'hospital rule

= lim x -> 9 d/dx(x²-81)/√x - 3

= lim x -> 9 2x/1/2√x

Substitute x = 9

= 2(9)/1/2√9

=18/1/(2(3)

=18 × 6/1

= 108

Hence the limit of the function is 108

7 0

3 years ago

In the diagram below,AB is the diameter of the circle with centre P.Point C lies on the y-axis.Given the coordinates of A and B

Step2247 [10]

Answer:

The coordinates of P are (-2,0)

The radius of the circle is 5.

Step-by-step explanation:

Analytic geometry

The diagram shows a circle with center P, and two points A(-6,3) and B(2,-3) that form the diameter of the circle.

The center of the circle lies at the midpoint of A and B. The midpoint (xm,ym) can be calculated by:

$\displaystyle x_m=\frac{x_1+x_2}{2}$

$\displaystyle y_m=\frac{y_1+y_2}{2}$

Substituting x1=-6, x2=2, y1=3, y2=-3:

$\displaystyle x_m=\frac{-6+2}{2}=\frac{-4}{2}=-2$

$\displaystyle y_m=\frac{3-3}{2}=0$

Thus, the coordinates of P are (-2,0)

b) The radius of the circle is the distance from the center to any point in its circumference. We can use the distance from P to A or B indistinctly.

Given two points A(x1,y1) and P(x2,y2), the distance between them is:

$d=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}$

Substituting x1=-6, x2=-2, y1=3, y2=0:

$r=\sqrt{(-2+6)^2+(0-3)^2}$

$r=\sqrt{4^2+(-3)^2}$

$r=\sqrt{16+9}=\sqrt{25}=5$

The radius of the circle is 5.

4 0

3 years ago