Question 201872
In order for {{{r^2-2r+k }}} to be factored, there must be two whole numbers that multiply to "k" AND add to -2. 



So let's pick a random number. I'm going to pick 12. Now what number must I add to 12 to get -2? Well, we can set up the equation {{{12+q=-2}}} and solve for "q" to get {{{q=-2-12=-14}}}



So the numbers 12 and -14 add to -2. They multiply to {{{(12)(-14)=-168}}}



So it turns out that the two numbers 12 and -14 both add to -2 (the middle coefficient) AND multiply to -168. So if we let {{{k=-168}}}, then the polynomial {{{r^2-2r-168}}} can be factored and it factors to {{{(r+12)(r-14)}}}



I'll let you find another value of "k". Simply use the logic used above to find another "k" value.