Question

Write the equation of the line with a slope equal to 1/3 and a y-intercept at (0,-1)

Answer 1

`y= (1)/(3) x-1`

Explanation:

Notice that they are giving to you not only the slope of the line, but its y-intercept, so we can use the "slope y-intercept" form of a line to give the answer.

Recall that the slope (m) y-intercept (b) expression of a line on the x-y plane is given by:

`y=mx+b` where "m" is the slope, and "b" the y-intercept"

In our case m = 1/3 , and the y-intercept is "-1", since the point (0,-1) corresponds to y = -1 when the x-value is "0".

The equation of the line then becomes:

`y=mx+b\\y=(1)/(3) x+(-1)\\y= (1)/(3) x-1`