HURRY PLZ

A system of equations is given below:

y = –2x + 1

6x + 2y = 22

Which of the following steps could be used to solve by substitution?

6x + 2(−2x + 1) = 22

−2x + 1 = 6x + 2y

6(−2x + 1) + 2y = 22

6(y = −2x + 1)

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.