I need help finding a function rule.

X Y

-4 -3

-2 0

0 3

3 answers

So your function rule would be as follows:

(-4,-3), (-2,0), (0,3)

Now use the formula to get the slope

m = (y2-y1)/(x2-x1)

(-4,-3) and (-2,0)

m = (0-(-3))/(-2-(-4))
m= 3/2
m=1.5

so this gives you
y = 1.5x +b

y= 1.5
x = 1

1.5 = 1.5 (1) = b
1.5 = 1.5 +b
b = 0

so your function is

f(x) 1.5x
All I need is a function rule. For example, y= 1/2x + -1
Each increase in x by +2 causes y to increase by +3. Therefore the function is a straight line of the form
y = mx = b and the slope is m = 1.5. Yopu still need to determine the constant term, b.
Use any point such as (x=0, y=3) to get b.
3 = 1.5*0 + b
b = 3
y = 1.5 x + 3