Question

Choose the point that lies on the graph of the piecewise function.

f of x equals negative the quantity of x plus 5 end quantity squared if x is less than or equal to negative 3 and equals 2x minus 5 if x is greater than negative

(-2, 9)
(-3, -11)
(-7, -4)
(-4, -13)

Answer 1

@jim_thompson5910

Answer 2

can you draw out the piecewise function?

Answer 3

yes I will try..

Answer 4

thanks

Answer 5

(-2, 9) means x = -2, y = 9

Answer 6

when x = -2, what inequality is being satisfied?

Answer 7

x greater than -3

Answer 8

x > -3

-2 > -3 ... replace x with -2


-2 > -3 is true, so you are correct

Answer 9

so you pick on the piece that corresponds to x > -3

Answer 10

that's the second piece, therefore

y = 2x-5 when x > -3

Answer 11

and you plug in x = -2

y = 2x - 5

y = 2(-2) - 5

y = -4 - 5

y = -9

we want +9 and NOT -9

So the point (-2,9) is NOT on the curve of this piecewise function

Answer 12

see how this process works?

Answer 13

yes I will try to find it and i will get back in a sec.. thx :)

Answer 14

It's B right?

Answer 15

wait or D

Answer 16

cuz I plugged in y=2(-3)-5 y=-11

Answer 17

wait, what is "y=2(-3)-5 y=-11" in reference to?

Answer 18

option 2

Answer 19

here is a graph of the piecewise function

Answer 20

pay very close attention to the endpoints (the open and closed circles)

Answer 21

now let's plot the points on this piecewise function

Answer 22

points A and D are clearly not on the graph, so they are out

B looks like it is on the graph, but it's actually in a hole, which is NOT part of the graph

only point C is on the graph

Answer 23

oh okay. how did you graph this what did you use

Answer 24

when x = -7, x <=-3 is true

y = -(x+5)^2

-4 = -(-7+5)^2 ... plug in (x,y) = (-7,-4)

-4 = -(-2)^2

-4 = -4 ... answer checks out

Answer 25

geogebra

http://www.geogebra.org/cms/en/

Answer 26

Do i need to download it?

Answer 27

I think you can download it or you can use the web-based version. So it's up to you which option works best. I prefer to download and install it so you can use it offline

Answer 28

oh okay, thanks! how do I do the wed-based version may I ask for a link for that

Answer 29

try this out

http://web.geogebra.org/chromeapp/

Answer 30

oh okay thank you so much! You've been most helpful! :))

Answer 31

you're welcome