When solving an application that involves two unknowns, sometimes it is convenient to use a system of linear equations in two variables.
Let c be any real number. If a = b, then a + c = b + cIf a = b, then a – c = b – c If a = b, then a ( c )= b ( c )If a = b, then a /c = b /c x + 7 – 7.
Applications of Linear Equations in Two Variables
