a car travels from point s at (-5,7) to point t at (-5,-1). if each unit represents 20 miles, how long will it take the car to travel this distance, traveling at 40 miles per hour?

The value is  

Step-by-step explanation:

From the question we are told that

  The initial  position of the car is  

   The final position of the car is    

    The speed of the car is

Generally the distance covered by the car along the x-axis is  

=>    

Generally the distance covered along the y-axis is  

=>

=>  

Generally the resultant distance covered is  

=>  

=>  

From the question we are told that 1 unit of the distance covered is  20 miles so  

    8 units is

=>        

Generally the time taken is mathematically represented as

=>    

=>    

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.

1/800 is the right answer