Question

What is the equation of the line that goes through the points (1,2) and (2,1)?

Answer 1

Answer:

y = -x+3

Step-by-step explanation:

We have two points so we can find the slope

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

    (1-2)/(2-1)

    -1/1

 The slope is -1

We can use the slope intercept form of the equation

y = mx+b where m is the slope and b is the y intercept

y = -x+b

Substitute a point into the equation to find b

2 = -1 +b

Add 1 to each side

2+1 =-1+1 +b

3 =b

y = -x+3