The first equation is 
(Equation 1)
The second equation is
(Equation 2)
Putting the value of x from equation 1 in equation 2.
we get,


by simplifying the given equation,


Using discriminant formula,


Now the formula for solution 'x' of quadratic equation is given by:


Hence, these are the required solutions.
Answer:
C.
Step-by-step explanation:
y = 1/ x must pass through the origin because when x = 0, y = 0.
So its either B or C.
A positive slope rises to the right ( 1/2 is positive), so its C.
You can also see that the slope of C is 1/2 because it passes through the points (0.0) and (2, 1).
For these kinds of expressions use FOIL (first, outside, inside, last).
-2x • 9x = -18x^2
-2x • -3y = 6xy
8y • 9x = 72 xy
8y • -3y = -24y^2
Now combine them all:
-18x^2 + 78xy - 24y^2
Answer: Rounded to the nearest tenth is 5
4.96894409 is the exact answer