How do you write a quadratic function in intercept form whose graph has x intercepts -4,1 and passes through (-3,-4)?

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Answer 1 · 2017-08-10T14:59:16

#f(x) = x^2+3-4#. For how, please see below.

Given that the #x# intercepts are #-4# and #1#, we know that the functions factors as

#f(x) = a(x+4)(x-1)#

Now we can use the fact that #f(-3) = -4# to find #a#

#-4 = a((-3)+4)((-3)-1)#

#-4 = a(1)(-4)# so #a = 1#

#f(x) = (x+4)(x-1)#

#f(x) = x^2+3-4#