text: Factor the numerator and the denominator out:\nr^2 -5r + 6 = (r - 3)(r - 2)\nr^2 - 4 = (r + 2)(r - 2) (A^2 - B^2 can always be factored to (A + B)(A - B)\n\nCross out the (r - 2)'s, and you have (r - 3)/(r + 2), or answer choice A.