how to tell if a graph represents a function

which graphs are functions? R^2 at SCC Determine whether a graph is a function. In this lesson you will learn how to tell if a line on a graph represents a function by mapping inputs to outputs. If each x value has a unique y value, then the graph represents a function. So in order for the points to represent a function, for every input into our function, we can only get one value. This test is called the vertical line test. In algebra, there are 3 basic types of graphs you'll see most often: linear, quadratic, and exponential. Simple. Graphs. We can easily determine whether or not an equation represents a function by performing the vertical line test on its graph. We can also represent functions using graphs by plotting all the ordered pairs of a function on a coordinate axis. if you know what y equals, say y = 2x. So if we look here, they've graphed the point--it looks like negative 1, 3, so that's the point negative 1, 3. Check out this tutorial and learn how to determine is a graph represents a linear, quadratic, or exponential function! We're asked: Do the points on the graph below represent a function? Instructional video. When a function is given as a graph, we have a nice test we can use to determine if the graph represents a function. If an algebraic equation defines a function, then we can use the notation f (x) = y. All points must lie along the curve for it to be a function. The easiest way to make a graph is to begin by making a table containing inputs and their corresponding outputs. Create your free account Teacher Student. In a table, if a value is given in the x table twice with separate y values, then it is NOT a function. Graphs come in all sorts of shapes and sizes. At the line which crosses the x axis at 3, y will = 6. Look at where the graph crosses the X-axis at the point [math]x=0[/math]. In a graph, we have what is called the vertical line test, in which if a vertical line crosses the graph in two or more points, then it is NOT a function. vertical line test to determine if a graph represents a function Put x into the equation, say 3, so y = 2*3 = 6. THE VERTICAL LINE TEST A graph (or set of points) in the plane is a FUNCTION if no vertical line contains more than one of its points. If any vertical line intersects the graph more than once, then the graph does not represent a function. Answer and Explanation: You can represent your function by making it into a graph. The [math]cos(0) = 1 [/math]and [math]sin(0)=0[/math]. For example, consider the function y = 2x + 1. , quadratic, and exponential to begin by making a table containing inputs and their corresponding.. Only get one value easily determine whether or not an equation represents function. Make a graph represents a function by performing the vertical line test on its.... 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