While there are many quadratic equations using -6 and 5 as roots, the most simple would be the basic (x+6)(x-5)=0, or simplified, x² + x - 30 = 0.
Using these roots, all you have to do is make both sides of the equation and even both sides of the multiplied pre-product to equal 0. If using this format, x has to be equal to -6, and 5.
