The graph of a quadratic function passes through the points (a-4, 0) and (a+2, 0), and the coordinates of the vertex are (5, -2). Find the value of a.

Question

sillybilly123 · Answer

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sillybilly123 · Answer

symmetry is your friend

sillybilly123 · Answer

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Enorym · Answer

How would you do this algebraically?

sillybilly123 · Answer

depends upon what you already know @Enorym

do you get the original point of the problem?

sillybilly123 · Answer

hey Voca !!

can you write a write an equation that singularly passes through all of these points?

Vocaloid · Answer

yikes

I'll try

if a - 4 and a + 2 are zeros, you can write an equation in factored form like

y = (x - (a-4))(x - (a+2))

you are given the point (5, -2) so you can plug these in for x and y to find a

^ I hope this works :S

dude · Answer

$y=c(x−5)2−2\

because ~it ~passes ~through ~(a-4,0) ~and ~(a+2,0)\
0=c(a-4-5)^2-2\
or ~c(a−9)2=2...(1)\
~\~
and\
0=c(a+2−5)2−2\
~\
or c(a−3)2=2...(2)\
~\
dividing (1) by (2)\
c(a−9)2c(a−3)2=1\
~\
(a−9)2=(a−3)2\
~\
a2−18a+81=a2−6a+9\
~\
a2−18a−a2+6a=9−81\
~\
−12a=−72\
~\
a=6$

Different explanation