# Unknown Story

#### Storyboard Text

• why do we need to study rational function? In what area of our life can we apply it?
• You can be in school because we think 1 teacher can hold 60 students because our number of teachers is limited
• We use rational functions in our daily lives, just like in cooking, we cannot just cook without measuring or estimating the proportion of each main ingredient we need, which depends on the amount of food we need to prepare.
• ow! really? Then, where else can we use rational function?
• So what about linear functions?
• So according to the web, Linear equations are an important tool in science and many everyday applications. They allow scientist to describe relationships-
• -between two variables in the physical world, make predictions, calculate rates, and make conversions, among other things.
• There are many such applications for linear equations. Anything that involves a constant rate of change can be nicely represented with a line with the slope. Indeed, so long as you have just two points, if you know the function is linear, you can graph it and begin asking questions!
• The equation of the linear function?A polynomial equation of the first degree (such as x=2y−7x=2y−7).
• Just make sure what you’re asking and graphing makes sense. For instance, in the marathon example, the domain is really only x≥0x≥0, since it doesn’t make sense to go into negative time and lose miles!