Question

Tell whether each function is quadratic. Explain. (0,6) (1,12) (2,20) (3,30)

Answer 1

alright so to find whether a function is quadratic or not, u have to do a whole bunch of junk
u only need 3 points to determine if a function is quadratic or not
\[ax^2+bx+c =y\]
so if we take the points (0, 6) (1, 12) and (2,20)
\[a(0)^2+b(0)+c = 6\]
\[a(1)^2+b(1)+c = 12\]
\[a(2^2)+b(2)+c = 20\]

Answer 2

@Laylalyssa

Answer 3

from here you know \[c = 6\]
\[a+b+c = 12\]
and \[4a+2b+c = 20\]
you can substitute the value for c in the other 2 equations as well

Answer 4

\[a+b+6=12\]
\[4a+2b+6=20\]
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\[a+b=6\]
\[4a+2b=14\]
We would want to eliminate one variable and solve for the other, think you can do it from here?
if u get a = 0 or the equations do not match the function is not quadratic

Answer 5

i think i got it now, thanks

Answer 6

np