Which of the following represents a valid first step to solving this system of equations using the substitution method?

2x – y = 7

x = 2y – 1

2x – y = 2y – 1

x = 2(2x – y) – 1

2x – (2y – 1) = 7

2(2y – 1)- y = 7

Which of the following represents a valid first step to solving this system of equations using the substitution method?

2x – y = 7

x = 2y – 1

2x – y = 2y – 1

x = 2(2x – y) – 1

2x – (2y – 1) = 7

2(2y – 1)- y = 7

Answer:Step-by-step explanation: