Yes, the graph would still be a function, but a different function than if the values were all different. This would cause two of the values to be the same and have no slope on the line. Before, the function was quadratic, but now it would be quadratic until the two values are equal.
1,3,and 4 because for 1 and 3 if you factor it out you can get (x+3)(x-7) which if you solve it it creates them to be -3 and 7. The 4 one is already factored you just solve it and it also becomes -3 and 7. The - outside the parentheses is nothing.
