Answer:
A. Trial and error
Step-by-step explanation:
Trial and error method is a method adopted when trying to solve a quadratic equation. This equation is mostly the balancing of the right hand side and the left hand side in-order to form a unique point or to equate to zero when one is subtracted from the other. In trail and error method, the coefficients is used to determine when the actual equation is balanced and the likely answer it should be if the equation is expanded through multiplication method.