Hart Corp. is considering a project that has the following cash flow data. What is the project's IRR?

Year Cash flows

$\backslash$table$[[0,1,2,3],[-$$$1,000,$$$425,$$$425,$$$425$

I need this shown through the formula, not show through excel. $13\mathrm{.}21$ is the correct answer, i just need to know how. Thanks