HELP ! pleaseee I’ve been trying & I still don’t know

Which of the following is correct interpretation of the expression -4+13

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

Solve each quadratic equation by factoring and using the zero product property. n^2 - 49 = 0