Billie solved the equation below by completing the square, but she got the incorrect solution. In which step did Billie first make an error? Choices: 1234

Step 1: x^2+10x=49

Step 2: x^2+10x+25=49

Step 3: (x+5)^2=49

Step 4: x+5=+-7

Step 5: x=2, x=–12