Question

Which parabola has the graph shown?

Answer 1

A

Answer 2

B

Answer 3

C

Answer 4

D

Answer 5

Okay, first thing to note is that the parabola opens to the side, not up or down, so it will be of the form y^2 = x rather than y = x^2

Answer 6

This means, by the way, that the relationship is not a function, because we can draw a vertical line that crosses the curve more than once.

Answer 7

ok got that

Answer 8

how can you tell which answer is correct?

Answer 9

Well, we can eliminate any that have x being squared — we need equations where y is squared.

Answer 10

D is out

Answer 11

leaves a,b,c

Answer 12

\[(x-3)=-(y+2)^2\]
ok
\[(x+4)=(y+1)^2\]
ok
\[(x+7)^2=(y+2)\]
not ok
\[(x+3)=(y+1)^2\]
ok

Answer 13

Now, can you tell me the vertex of the parabola?

Answer 14

brb, I'm cooking dinner

Answer 15

no i cant. can i just get the answer and explain it after?

Answer 16

i think C

Answer 17

the vertex is the point at the bottom of the bowl.

Answer 18

because -3,-1

Answer 19

or the end, as the case may be

Answer 20

its like where the graph is at so is that the answer?

Answer 21

i mean parabola

Answer 22

looks like (-4,-1) to me, do you agree?

Answer 23

oh yes i see it now. B fulfills it

Answer 24

that vertical line is the directrix, and the dot is the focus, they are symmetric about the vertex (same distance away)

the vertex is an obvious point to try in the equations.