The product of 6 and a number is the same as 40 less than twice that same number. find the number. the answers are 4,20,-20,-4

Taking algebra two apex courses and need with these questions

Can someone me and do the problem plz so i can understand it more better

Eric has challenged himself to walk 24,000 steps in 4 days. if eric walks the same number of steps each day, which function represents the number of steps eric still needs to walk to reach his goal with respect to the number of days since he started his challenge? a. y = 8,000x − 24,000 b. y = -8,000x + 24,000 c. y = 6,000x − 24,000 d. y = -6,000x + 24,000