Question 7 of 10 If you were to solve the following system by substitution, what would be the best variable to solve for and from what equation? \( 2 x+6 y=9 \) \( 3 x-12 y=15 \) A. \( x \), in the first equation B. \( y \), in the first equation C. \( x \), in the second equation D. \( y \), in the second equation SUBMIT

To solve the system of equations by substitution, we need to choose a variable to solve for and an equation to use for substitution. Given equations: 1. \(2x + 6y = 9\) 2. \(3x - 12y = 15\) Let's analyze the options provided: A. Solving for \(x\) in the first equation: \(2x + 6y = 9\) \(2x = 9 - 6y\) \(x = \frac{9 - 6y}{2}\) B. Solving for \(y\) in the first equation: \(2x + 6y = 9\) \(6y = 9 - 2x\) \(y = \frac{9 - 2x}{6}\) C. Solving for \(x\) in the second equation: \(3x - 12y = 15\) \(3x = 15 + 12y\) \(x = \frac{15 + 12y}{3}\) D. Solving for \(y\) in the second equation: \(3x - 12y = 15\) \(-12y = 15 - 3x\) \(y = \frac{15 - 3x}{-12}\) Based on the options provided, the best variable to solve for and from which equation would be: A. Solving for \(x\) in the first equation.