To determine the solution to the system, we use substitution method.
Substitute the y of the second equation to the y of the first equation.
Second equation: 2x + y = -1
y = -1 - 2x
Substituting to the first equation,
x² - (-1 - 2x) = 4
Simplifying,
x² + 1 + 2x = 4
x² + 2x -3 = 0
The values of x from the equation are -3 and 1.
ANSWERS: x = -3 and x = 1