Find the function rule.

Question

I'm having a very hard time on this question..

x: -2, -1, 0, 1, 2

y:  9,  4, -1, -6 ,-11

 

Answer 1

y=-5x-1

 

x        y

-----------

-2      9

-1      4

0      -1

1      -6

2     -11

Answer 2

slope (m) = change y: (9-4) / change x: (-2-(-1))

slope (m) = -5

 

y = -5x + b

4 = -5(-1) + b          substitute one pair

4 = 5 + b                 multiply

-1 = b                      subtract 5 from both sides

 

y = -5x - 1