Final answer:
To produce opposite coefficients for x or y, multiply the first equation by -1 and the second equation by 4.
Step-by-step explanation:
To produce opposite coefficients for x or y, we can multiply the first equation by -1. This gives us: -4x - 5y = -7. Multiplying the second equation by -1 would give us the same equation as the first one. However, the goal is to produce opposite coefficients, so we multiply the second equation by 4. This gives us: -12x + 8y = 48.
Learn more about Multiplying equations by a number to produce opposite coefficients