Quadratic function in standard form from sets of points?

please help and explain! thanks youuu!





Find a quadratic function in standard form for each set of points.





1. (0, 3) (1. -4) (2, -9)


(all i know is that c=3, right?)





a. f(x)= x^2+27x + 3


b. f(x)= x^2 -27x + 3


c. f(x)= x^2 +8x -3


d. f(x)= x^2 -8x + 3








2. (0, -4) (1, 0) (2, 2)





a. f(x)= -2 x^2 +5x -4


b. f(x)= -x^2 -5x +4


c. f(x)= -x^2+5x -4


d. f(x)= -x^2 +5x +4

Quadratic function in standard form from sets of points?
They are multiple choice question, so you can substitute and check.





1. First points satisfies all euqtions


so check with (1, -4)


1 + 27 + 3 = 31 not equal to -4 so its not a


1 - 27 + 3 not equal to -4 so its not b


1 + 8 - 3 not equal to -4 so its not c


1 - 8 + 3 is equal to -4 so its d





So the answer is d. Now if you want you can chcek with the third point.


4 - 16 + 3 = -9 so now you are sure its d





2. substitue (0, -4) from this you know it cannot be b, d as they will result is f(0) = 4


so it has to be a, d





Substitute (1, 0) in a


-2 + 5 - 4 = -1 not equal to 0 so its not a


in c, -1 + 5 - 4 = 0 so its c


Answer is c