Question

The equation of the line that goes through the point (2,2) and is parallel to the line going through the points (-1,6) and (1,5) can be written in the form y=mx+b where m is what and b is what?

Answer 1

• m = -1/2
• b = 3

Explanation:

You want the slope-intercept equation of the line through (2, 2) and parallel to the line through (-1, 6) and (1, 5).

Slope

The parallel line will have the same slope. The slope is given by the equation ...

m = (y2 -y1)/(x2 -x1)

m = (5 -6)/(1 -(-1))

m = -1/2

Intercept

We need to find the y-intercept of the desired line. Solving the equation for "b", we get ...

y = mx +b

b = y -mx . . . . . . . subtract mx to find b

b = 2 -(-1/2)(2) . . . . use m=-1/2 and (x, y) = (2, 2)

b = 2 +1

b = 3

The equation we want is ...

y = -1/2x +3