Definition of Substitution Method. One way to solve systems of equations is by substitution. In this method, solve an equation for one variable, then substitute that solution in the other equation, and solve.
Area code 407 is found in the US state of Florida. Primarily servicing the city of Orlando (population: 921360), area code 407 covers 5 counties of Florida.Located in the Eastern time zone, area code 407 is on the same time as New York, NY. Area code 407 was brought into effect on April 16, 1988.407 was split from the parent 305 area code.rimarily servicing the city of Orlando (population: 921360), area code 407 covers 5 counties of Florida. Located in the Eastern time zone, area code 407 is on the same time as New York, NY.
California area codes. The map above is clickable; click on an area code to go to the page for that area code. The area code in red is area code 209; all others in blue are California area codes.Area code 209 is the California telephone area code that was split from area code 916 on October 26, 1957.rea code 209 is the California telephone area code that was split from area code 916 on October 26, 1957.