What is the solution set of this system of equations?
y = x2 − 3x − 4
x = y + 8

a.{(-1, 0), (4, 0)}
b.{(8, 0), (0, 8)}
c.{(0, 0)}
d.{(2, -6)}
e. there is no real solution.

me, i'm afraid i will fail. no "solve it yourself" answers. you guys so much! < 3

Option: d is the correct answer.

The solution set of this system of equations is:

             d.   {(2, -6)}

We are given a system if equations by:

and  

i.e.

Also, from equation (2) we get:

Hence, the solution set is:  {(2,-6)}

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.