Basically they are subbing x with the letter z
The four-fifths of a number, in this case, z is four times the number divided by z. That is 4z/5. When we add six to the product and equate the expression to 8, we get,
4z/5 = 8
The value of z from the equation is 10.
It is an odd-degree polynomial. Therefore...
As the coefficient is negative for x^9.
When x < 0 or x approaches negative infinity, y or f(x) will approach positive infinity.
When x approaches positive infinity, y or f(x) will approach negative infinity.
So it is the second and the third.
The answer is C
12 * 4 = 48, 180 - 48 = 132
I hope this helps :)