##### Item1.3.5.2.a.i

How many cars per hour enter the upper left intersection? How many cars per hour leave this intersection? Use this to form a linear equation in the variables \(x\text{,}\) \(y\text{,}\) \(z\text{,}\) and \(w\text{.}\)

How many cars per hour enter the upper left intersection? How many cars per hour leave this intersection? Use this to form a linear equation in the variables \(x\text{,}\) \(y\text{,}\) \(z\text{,}\) and \(w\text{.}\)