Question

Malia is using an online calculator to calculate the outputs f(n) for different inputs n. The ordered pairs below show Malia's inputs and the corresponding outputs displayed by the calculator:

(1, 4), (2, 9), (3, 14), (4, 19)

Which of the following functions best represents the rule that the calculator uses to display the outputs?

f(n) = 5n - 1

f(n) = 5n + 1

f(n) = 4n + 1

f(n) = 4n - 1

Answer 1

@jigglypuff314

Answer 2

find the slope between two points
do you know how to do that?

Answer 3

y2-y1 over x2-x1

Answer 4

i got 5 as my slope

Answer 5

correct :)
now y = mx +b you got m=5
so y = 5x + b right?

then temporarily plug in a point (x, y)
and solve for b

Answer 6

okay

Answer 7

okay i did 9=5(2) + b

Answer 8

yep :) and try to solve for b from that ^_^

Answer 9

i got -1=b

Answer 10

that is correct :)
now can you take a guess for what your answer might be? :P

Answer 11

A :), thanks!! do you mind if i post some questions that i dont understand and tag you?

Answer 12

sure, I don't mind :)