Question

Find the vertex of the graph of the quadratic function. f(x) = x²-14X-7 O A. (7-56) OB. (-14, - 7) Oc. (7. - 154) OD. (-7,42)

Answer 1

Solution given that quadratic equation is F(x) = - 22-14X-7 we knows that standard form of quadratia Function is Fool) = a(x-h) 2+k 0 her vertex is (hik) so First , ule weill change this into standard form FIX) = 22-143-7 F(nl) = - (x?+ 14x+7) -1 22721744) +7) F(x) = we know that a? +210)16) + b2 = (a+b)2 here a = a) b = 7 so add - 72 = 49 and subtreet Fla) -( ? + 2(30)17) + 49 +7-49) = Flac) [(x2 + 2(x) (1) +49)- 42] F(X) = - [(x+7)2- 42] F1%) = -1/2+7)? + 42 -|(x++)? + 42 So her compare this to equation h = -7, K= 42 so vertex is (-7,42)