Question

If y = 5x − 4, which of the following sets represents possible inputs and outputs of the function, represented as ordered pairs?

{(0, −4), (2, 6), (4, 20)}
{(0, −4), (2, 6), (4, 16)}
{(0, 4), (2, 6), (4, 16)}
{(0, 4), (2, −6), (4, 20)}

Answer 1

I still don't understand how to do this stuff. @Shadow @Allison @Elsa213

Answer 2

take it one point at a time, one answer choice at a time

(0, -4)

this means that the input of 0 gives an output of -4

to test whether this is true, let x = 0 and see if y = 5x − 4 gives -4 as its output

if yes: the point is on the line, test the next point within the same answer choice
if not: the point is not on the line, move to the next answer choice

Answer 3

Oh okay, so that's not the answer?

Answer 4

I haven't said anything about whether it's the answer or not, you still have to go through the calculations

see if x = 0 gives an output of -4

Answer 5

Okay, that one is not it. Because 5 + -4 = 1 not 0

Answer 6

x is the input not the output

if x = 0, y = 5(0) - 4 = ?

Answer 7

1?

Answer 8

5*0 = ?

Answer 9

I am so confused right now.

Answer 10

what is 5 times 0 ?

Answer 11

5

Answer 12

i mean 0

Answer 13

good, so 5(0) - 4 = -4 meaning that (0,-4) is one of the correct ordered pairs, meaning we can eliminate C and D as possible answers

now we test whether (4,20) or (4,16) is an ordered pair on the line

Answer 14

y = 5x - 4

if x = 4, what does y equal?

Answer 15

umm... i don't know. I feel like an idiot.

Answer 16

x = 4 means you can replace "x" with 4" when x shows up

so y = 5x - 4 = 5(4) - 4 = ?

Answer 17

5(4) that equals 20

Answer 18

good, and then subtract 4 from that

Answer 19

16

Answer 20

awesome, so (4,16) is another point on the graph eliminating A and making B the correct answer

Answer 21

(:

Answer 22

So, the answer is B? or is there another step?

Answer 23

it's B, that's all

Answer 24

Thank you, so much! ur a life saver.

Answer 25

LOl!