Sindhu successfully solved the system of equations 3x+y=9 and −2x−y=−7. Which of these statements could correctly describe what she did?
A
She added the two equations together to solve for x, and then she substituted the value of x back into one of the equations and solved for y, getting x = 2 and y = 3.
B
She added the two equations together to solve for x, and then she substituted the value of x back into one of the equations and solved for y, getting x = 3 and y = 2.
C
She added the two equations together to solve for y, and then she substituted the value of y back into one of the equations and solved for x, getting x = 2 and y = 3.
D
She added the two equations together to solve for y, and then she substituted the value of y back into one of the equations and solved for x, getting x = 3 and y = 2.
D
She added the two equations together to solve for y, and then she substituted the value of y back into one of the equations and solved for x, getting x = 3 and y = 2.