Final answer:
To solve the system of equations, use the substitution method. Substitute the value of y in the second equation. Solve the resulting quadratic equation for x. The correct answer is x = -0.79 (option b).
Step-by-step explanation:
To solve the system of equations for x, we can use the method of substitution or elimination. Let's use the substitution method. First, let's solve the first equation for y: y = -2x - 1. Now, substitute this expression for y in the second equation: 4(-2x - 1) - 4x^2 - 12x = -7. Simplifying, we get: -8x - 4 - 4x^2 - 12x = -7. Rearranging, we have 4x^2 + 20x - 3 = 0. Solve this quadratic equation using the quadratic formula or factoring, and round x to the nearest hundredth.