The answer is -4,7
The denominator can't equal zero. Factor the denominator:
x^2 - 3x - 28=
(X - 7)(x + 4); next set each set of parentheses equal to 0;
x - 7 = 0; so x=7 is one value
x + 4 = 0; so x=-4 is the other
Remember, x = 7 and x= -4 make the denominator zero, which is a "restriction" because you can't divide by zero.
