How do I write the standard form when a graph is given?

Question

Write the standard form of the graph with the points (0,3) and (-2,-1).

Answer 1

With two points you can make a line

y = mx +b

The slope (m) can be found as the ratio of the "rise" over the "run" or (y₂ - y₁) / (x₂ - x₁).

using point #1 as (0,3) and point #2 as (-2,-1)

m =( -1 - 3)/(-2 - 0 ) = 2

y = 2x + b

Now choose one of the two points and solve for b...

3 = 2(0) +b --> b = 3

y = 2x + 3