There are various ways to obtain the line equation from a point (x<sub>1</sub>, y<sub>1</sub>) and the slope m, such as using the point-slope formula:
. . . . .y - y<sub>1</sub> = m(x - x<sub>1</sub>)
Plug your point and slope into the formula, and then rearrange to get whatever your book is calling "standard form".
Eliz.