Answer:
1) after 4 weeks, Lin has more with $65
2) after 3 weeks they both have same amount
Step-by-step explanation:
let 'w' = number of weeks
1) equation for Han: y = 100 - 15w
y = 100 - 15(4)
y = 100 - 60
y = $40 after 4 weeks
equation for Linn: y = 25 + 10w
y = 25 + 10(4)
y = 25 + 40
y = $65 after 4 weeks
2) 100 - 15w = 25 + 10w
75 - 15w = 10w
75 = 25w
w = 3 weeks