Slope-intercept form: y = mx + b
(m is the slope, b is the y-intercept or the y value when x = 0 --> (0, y) or the point where the line crosses through the y-axis)
x = the number of weeks she mows the lawn
y = the amount of money in Jana's savings account
y = 25x + 125
[amount of money in savings account(y) = $125 plus $25 per week(x)]
y-intercept = 125
So if x = 0 weeks and y = $125 in the savings account, $125 was already/initially in the savings account before she started earning and depositing $25 per week. Your answer is C