How to Evaluate Function Expressions Using Graphs

Miacademy & MiaPrep Learning Channel

This educational video serves as a clear, step-by-step tutorial on how to evaluate mathematical expressions involving function notation using graphs. Hosted by a narrator named Justin, the video builds upon prior knowledge of reading function graphs to tackle more complex problems where students must substitute values derived from graphs into arithmetic expressions. It transitions from simple discrete graphs to systems involving multiple continuous functions on the same coordinate plane, demonstrating how to distinguish between different function names like f(x) and g(x). The key themes explored include function notation, interpreting graphical data, substitution, and order of operations. The video specifically emphasizes the process of "finding and replacing" function outputs with their numerical values before simplifying the expression. It addresses potential student anxiety regarding complex-looking equations by breaking them down into manageable steps of identifying inputs and outputs on a grid. For educators, this video is an excellent resource for Algebra I or II classes. It visually connects abstract algebraic notation with concrete graphical representations, helping students visualize what f(x) actually means. The clear color-coding and distinct examples make it useful for introducing the concept of evaluating composite expressions or for reviewing function literacy before moving on to word problems or calculus concepts.