



 
Hi Salehah, If a is an xintercept, then f(a) = 0 and (xa) is a factor. This is one of the most important things to know about polynomials. Remember it's minus, not plus! So if 2 and 4 are both xintercepts, you know two factors, and that's all a quadratic has. So, up to a multiplicative constant , you know the answer. Write it down... and remember that Now, what is the yintercept of your quadratic  that is, f(0)? If it's 4, you're done (but it isn't if you did everything right up till now). So multiply by whatever you need to in order to get the right yintercept; this won't change the xintercepts of course. Good Hunting!  


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