Question

PLEASE HELPPPPP

For the first picture determine the equation of the parabola shown in the diagram in vertex form and for the second picture determine the equation of the parabola shown in the diagram in factored form.

Answer 1

see explanation

Explanation:

the equation of parabola in vertex form is

y = a(x - h)² + k

where (h, k ) are the coordinates of the vertex and a is a multiplier.

here (h, k ) = (3, 1 ) , then

y = a(x - 3)² + 1

to find a substitute any other point on the graph into the equation.

using (0, 7 )

7 = a(0 - 3)² + 1 ( subtract 1 from both sides )

6 = a(- 3)² = 9a ( divide both sides by 9 )

`(6)/(9)` =
`(2)/(3)` = a

y =
`(2)/(3)` (x - 3)² + 1 ← in vertex form

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the equation of a parabola in factored form is

y = a(x - a)(x - b)

where a, b are the zeros and a is a multiplier

here zeros are - 1 and 3 , the factors are

(x - (- 1) ) and (x - 3), that is (x + 1) and (x - 3)

y = a(x + 1)(x - 3)

to find a substitute any other point that lies on the graph into the equation.

using (0, - 3 )

- 3 = a(0 + 1)(0 - 3) = a(1)(- 3) = - 3a ( divide both sides by - 3 )

1 = a

y = (x + 1)(x - 3) ← in factored form