Question

Fan for answer!

The table below represents a linear function f(x) and the equation represents a function g(x):


x f(x)
−1 −5
0 −1
1 3
g(x)

g(x) = 4x + 3



Part A: Write a sentence to compare the slope of the two functions and show the steps you used to determine the slope of f(x) and g(x). (6 points)

Part B: Which function has a greater y-intercept? Justify your answer. (4 points)

Answer 1

@saseal Can you help?

Answer 2

You know how to find the equation of f(x)?

Answer 3

Not really sorry... Is it m = y2 - y2 over x2 - x1 ?

Answer 4

yes take 2 of the points and plug em into the formula
\[m=\frac{ y _{2} - y _{1} }{ x _{2} - x _{1} }\]

Answer 5

What do you mean when you say two points?

Answer 6

Value of f(x) is your y

Answer 7

so you have 3 points of the line here (-1,-5) , (0,-1) ,(1,3)

Answer 8

Oh I understand what you are saying thank you, so I just plug all those in function by function right?

Answer 9

yes

Answer 10

OK give me a min

Answer 11

you plug in the numbers into the formula for gradient

Answer 12

just choose any 2

Answer 13

Well I got one that is 0 - (-1) over -1 - (-5) that equals 4 would that be my slope?

Answer 14

yea so the line equation we have now is
\[f(x) = 4x+c\]

Answer 15

now we can find the value of c by replace the value of f(x) and x

Answer 16

Oh ok thank you so much for your help do you need anything?

Answer 17

you got your answer?

Answer 18

Almost

Answer 19

c is the y-intercept of the line

Answer 20

It's given to you actually, look at x = 0 f(x) = -1

Answer 21

Because:
\[4(0)+c=-1\]

Answer 22

ok ok

Answer 23

I get it sorry I was stuck you need anything?

Answer 24

Nah not really.

Answer 25

Well thanks for all the help!

Answer 26

You're welcome