No they do not. the order of operations (GERMDAS) says that you divide and multiply before adding or subtracting. This means that without the parentheses, the answer is 15. with the parentheses, because you solve what is in the parentheses first, the answer is 9.
I believe so because if you were to work them out it would give you the same answer. the parentheses don't make the probably different since it doesn't have an exponent. so they are not needed
Another term for the roots or x-intercepts of the standard-form quadratic equation is "<em>solutions</em>." These are the values of x that make the equation true.
