Respuesta :
Given that the vertex (h, k) is (5, 2), you know the vertex form will look like
f(x) = a(x -5)² +2
for some value of "a" that makes f(4) = -3. That value of "a" can be found by substituting the given values in the above equation for f(x) and solving for "a".
-3 = a(4 -5)² +2
-3 -2 = a×1²
a = -5
This means the appropriate choice is ...
C) Vertex form: f(x) = -5(x -5)² +2; Standard form: -5x² +50x -123
f(x) = a(x -5)² +2
for some value of "a" that makes f(4) = -3. That value of "a" can be found by substituting the given values in the above equation for f(x) and solving for "a".
-3 = a(4 -5)² +2
-3 -2 = a×1²
a = -5
This means the appropriate choice is ...
C) Vertex form: f(x) = -5(x -5)² +2; Standard form: -5x² +50x -123