Explain how john locke's political ideas could be used to justify the american revolution

This isn't going to be pretty good sized but it will get you started. 

Locke wrote that all men are equal and that they have the natural right to defend their "Life, health, liberty, or possessions." This was stolen from Locke for use in the Declaration of Independence by Jefferson when he penned , "Life, liberty and the pursuit of happiness." 

Locke's social contract also described the role of government. He felt government should perform the will of the people and when it doesn't -- it is the people's right/duty to overthrow said government.

Locke championed the social contract which includes the ideas of "government with the consent of the governed", rights of life, liberty and property." The founders were well versed in the writing of John Locke and other enlightenment philosophers, who were also influenced by Locke.

Hope this helped. Have a great day!