If you were to use the substitution method to solve the following system, choose the new equation after the expression equivalent to x from the first equation is substituted into the second equation.
x + 4y = −9
2x + 5y = −6
2x + 5(4y − 9) = −6
2x + 5(−4y − 9) = −6
2(4y − 9) + 5y = −6
2(−4y − 9) + 5y = −6