The parent function of any a quadratic function is
Use FOIL
28x² -8xy +7xy -2y²
28x² -xy -2y²
5x + 8y = -29
7x - 2y = -67 ..... multiply both sides by 4
5x + 8y = -29
28x - 8y = -268
33x + 0y = -297
x = -9
(-9, 2)
For the first equation, the answer is C) completing the square.
For the second equation, the answer is B) zero product property.
For the first equation, we can easily complete the square by finding half of b and squaring it; then we can take the square root of both sides and solve the equation.
For the second equation, since it is already factored, we use the zero product property to solve it.