ACT Preparation / Unit 9 ACT 0816 short lesson, about 20 seconds
Slope and Intercept in a Model
Captions available
The idea
In a linear model, the slope is the rate of change, with units, and the y-intercept is the starting value, when the input is zero.
In practice
For a plumber's bill, C = 45 + 30h: 45 dollars is the visit fee, and 30 dollars is the charge per hour.
Where people slip
Name the units: the slope here is dollars per hour, not dollars.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
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