Write an equation of a line in slope-intercept form with two ordered pairs of (1, 13) and (2, 21).

Use this fraction:21-13
                            2-1
That goes to 7/1, or 7. The slope is 7.
Use the equation y=mx+b
y=7x+b
substitute x and y for numbers
13=7(1)+b
Simplify
13=7+b
Subtract 7 from both sides
6=b
The equation in slope intercept form=
y=7x+6