1) If x is the number of years Naicul works, then the corporate job would earn him
49600x + 2000
dollars, while the teaching job would earn
50000x
dollars. Solve for x such that these two earnings are equal:
49600x + 2000 = 50000x
400x = 2000
x = 5
2) a) At a speed of 6.7 m/s, DJ would finish the race in
(100 m) / (6.7 m/s) ≈ 14.93 s
2) b) If DJ is given a headstart of y seconds, then Usain finishes the race in (9.58 + y) seconds. Solve for y such that this time matches DJ's time from part (a) :
14.93 s = (9.58 + y) s
y ≈ 5.35 s