I need to write the slope-intercept equation for a line that passes through the points (-3,0) and (3,1).

y=mx+b, so using y1-y2/x1-x2 I get a slope of 1/6, changing the equation into y=1/6x+b

How do I find b?

Question

I need to write the slope-intercept equation for a line that passes through the points (-3,0) and (3,1).

y=mx+b, so using y1-y2/x1-x2 I get a slope of 1/6, changing the equation into y=1/6x+b

How do I find b?

amistre64 · Answer

or to relate it to finding slope ... we can progress thru these steps
$$\frac{y-Py}{x -Px} = m$$
$$y-Py = m(x -Px)$$
$$y-Py = mx -mPx$$
$$y = mx -mPx+Py$$
$$y = mx +[-mPx+Py]$$
$$y = mx +b$$

anonymous · Answer

Can Py be any of the y variables in the two given points? Likewise for Px?

amistre64 · Answer

in a sense, yes; but make sure your Py and Px are from the same given point :)

amistre64 · Answer

once you know: y=mx+b, you can actually find "b" by using either given point as well.

Py = m(Px) + b
Py - mPx = b; which amounts to what i wrote above i believe