Do you need to solve this problem with paper and pen or can you use a calculator, program, or website?
If you need an analytical solution, or pen-and-paper, another way to attack this type of problem would be to use the Quadratic Formula (QF); there is a lot of good material about the QF on Wikipedia or MathWorld. This approach is easier if you have a calculator, but it allows for exact, algebraic, solutions.
On the other hand, if you cannot solve the problem easily, you might not have a choice but to use the QF.
And if you are allowed to use a program or web applet, then you can solve the problem numerically.
For example, here is a free online applet that solves a Quadratic Equation:
Quadratic Equation Solver Whether you use a web program, a full-blown computer program, or a pocket calculator, once you have numeric solutions root1 and root2, you could then re-state the original equation in the following form:
(t - root1)(t - root2)
If the roots are nice round numbers, that is nice but doesn't always happen. The solutions are what they are.