A car covers a distance of 60 km in 3 hours. However, for the first 40 km it travels 16 km/hr. At what speed must it travel for the rest of the distance in order to complete the journey on time?

40 km/hr

Step-by-step explanation:

Given that:

Total distance covered in 3 hours = 60km

Speed during first 40 km = 16km/hr

Hence, time spent during the first 40 km ;

Recall:

Time = distance / speed

Time = 40 / 16

Time = 2.5 hours

Hence, speed required to cover the remaining (60 - 40) = 20km in (3 - 2.5) hours =0.5 hours

Speed = distance / time

Speed = 20 / 0. 5

Speed = 40 km / hr

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.

all the angles opposite to the angle 150 would be 150 and all the angles that are next to 150 are 30 because they equal 180 it you add it up.

step-by-step explanation: