Algebra 2: 1.5-1.7

Slope-Intercept Form

y=mx+b

Point-Slope Form

y-y1=m(x-x1)

Standard Form

Ax+By=C

Slope Formula

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

x-intercept

where the line crosses the x axis. set y=0 and solve for x

y intercept

where the line crosses the y-axis. set x=0 and solve for y

writing an equation from a graph

identify a one clear point on the line, find the slope(RISE OVER RUN) between two visible points. plug point and slope into point-slope form, simplify to slope-intercept form, and then change to standard if asked

writing equation from two points

1) find slope using both points: m+(y2-y1)/(x2-x1). 2) pick either point and plug it, with the slope, into point slope form. 3) simplify into the form requested(slope-intercept unless told otherwise.

writing an equation from a table

pick any two rows and use them to calculate the slope. check the slope with a third row, should be same if linear, then use one row as your point and write the equation, same as two point method above.