Which equation represents a parabola opening to the left with a vertex at the origin and a focus at (-7, 0)? a. x=1/28 y^2 b

Question

Which equation represents a parabola opening to the left with a vertex at the origin and a focus at (-7, 0)?

a. x=1/28 y^2
b. x= – 1/28 y^2
c. y= 1/20 x^s
d. y= – 1/20 x^s​

in progress 0
Rylee 2 weeks 2021-09-13T16:12:30+00:00 1 Answer 0

Answers ( )

    0
    2021-09-13T16:14:26+00:00

    Answer:

    b. x=1/28 y^2

    Step-by-step explanation:

    the standard equation,

                          y^{2} = 4ax  —(1)    , when opening towards left or right

                          focus at (a , 0)

                          x^{2} = 4ay —(2)      , when opening towards top or bottom

                          focus at (0,  a)

                                                 

    if a is negative parabola will open toward negative axes ( down or left) and vice versa.

    re- arranging option b. we get

                            y^{2} =28 x\\y^{2} = 4 X (-7 x) —–(3)

    therefore, a =  -7

    (3) is similar to (1)

    So it is facing left with focus at (-7,0)

Leave an answer

Browse
Browse

27:3+15-4x7+3-1=? ( )