A product of two numbers is the result we get from multiplying them together. The product of 4 and x would then be [tex]4\times x[/tex], which we can rewrite as [tex]4x[/tex]. We're then told by the statement "one minus the product..." that we'll be taking this [tex]4x[/tex] away from 1, giving us the answer [tex]1-4x[/tex].
