Practice!

Sample Problem

A line goes through the point (1, 1) and has a slope of -2. Write the equation of this line in slope-intercept form.

y = x +

Solution

A linear equation of a slope-intercept form y = mx + b , m is the slope and b is the y-intercept.

We know the slope and a point on the line, so we can plug m =-2,  x = 1,  y = 1, into  y = mx + b and solve for b.

1 = -2(1) + b; b = 3.

The equation of this line is therefore y = -2x + 3.