(Solved): Use the vertical line test to determine whether or not the graph is a graph in which y is a functio ...

Use the vertical line test to determine whether or not the graph is a graph in which y is a function of $$x$$. Evaluate the function $$f(x)=x^2+4x?3$$ at the given values of the independent variable and simplify. a. $$f(?3)$$ b. $$f(x+7)$$ c. $$f(?x)$$ a. $$f(?3)=$$ (Simplify your answer.) b. $$f(x+7)=$$ (Simplify your answer.) c. $$f(?x)=$$ (Simplify your answer.)