Thermal Expansion, Change in Temperature

[Sun44]

Homework Statement

""If the coefficient of thermal expansion of steel is 1.1 x 10^ -5 ℃^ -1 and a railway rail is 4. 5 m long, how much would the length Δ L of the rail increase by if the temperature changes from -10 ℃ to 30 ℃? ""

Could anyone direct me to a youtube video, or something that could help understand how to work this out and get the answer.

Homework Equations

Im not sure

The Attempt at a Solution

Not sure. Please and thank you for your help.

 

[Doc Al]

See: http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/thexp.html"