Question

What are the steps for finding a function rule, if you are given the graph of a function?

Answer 1

Find the slope (m), and y-intercept (b), then its y=mx+b

Answer 2

I need the steps, not the formula.

Answer 3

oh so it is a linear function?

Answer 4

@runner51 it says "function rule" and "graph of function" not "equation for line" and "graph of a line"

Answer 5

if it is the latter, then you can do it by
1) locating the point at which the graph crosses the \(y\) axis. if it crosses at \((0,b)\) then that is your \(b\) in \(y=mx+b\)

2) find the slope of the line by computing the change in \(y\) over the change in \(x\)

Answer 6

you have to decided on the rule to get from the input numbers to the output numbers (and it has to be the same for ALL of them).
so if our t-chart looks like this:
INPUT OUTPUT
1..............3
2..............5
3..............7
4..............9
5.............11

then we put in an input number, multiply it by 2 and add 1 to get the output number (and it works for ALL of the pairs).
so if we say that x is the input number then f(x) is the output and our rule would look like this:
f(x) = 2x + 1

(the output is 2 times the input plus one)

this can be graphed as a straight line