Question

How do you find the value of a in a parabola?

Answer 1

given what?

Answer 2

given the formula fx=a(x+b)(x-c)

Answer 3

fx or f(x)?

Answer 4

yes its f(x)

Answer 5

got any specific values by any chance?

Answer 6

there are 3 unknowns (4 actually), and only one equation, i need more values

Answer 7

or constraints

Answer 8

Im trying to get a picture of it

Answer 9

what class is this for?

Answer 10

its for algebra

Answer 11

algebra 2/trig?

Answer 12

algebra 1

Answer 13

do you want an answer or an explanation?

Answer 14

answer please

Answer 15

and elxplination

Answer 16

parabola equation +

y=ax^2+bx+c
solve for a
a=-b/x-c

Answer 17

rewrite as a parabola

Answer 18

put in given variables to create three equations with three unknowns

Answer 19

0 = a-b+c
0 = 9a+3b+c
8 = a+b+c

Answer 20

solve for a and you will get -2

Answer 21

the entire equation can be rewritten as: -2x^2 + 4x + 6 = f(x)

Answer 22

or factor into -2(x+1)(x-3)

Answer 23

and thats it

Answer 24

anwarullah can u give me best response plz i need medals lol

Answer 25

No you don't.

Answer 26

what exactly is the question?

Answer 27

How do find the vertex?

Use -b/2a to find the x-value, then plug this back into the equation to find y.

How do you know if the parabola opens upward or downward?

If leading coefficient is positive then it opens upward -- if negative then downward.

How do you find the x-intercepts?

Set equal to zero and solve. Use quad formula or complete the square, etc.

How do you find the line of symmetry?

Again, using -b/2a also equals the line of symmetry.

How do you find the maximum or minimum value?

This is the same as the vertex. If open upward then it is a MIN value, if downward it is a MAX.