Answer:
y = -x + 3
Step-by-step explanation:
The equation of a straight line is generally written as;
y = mx + b
where m is the slope and b is the intercept
To get the slope we use the slope formula
Mathematically, that is;
m = (y2-y1)/(x2-x1) = (-1-2)/2-1 = -3/1 = -1
To get the intercept we equate any of the points to the partial equation that we have;
From;
y = -x + b
2 = -1 + b
b = 1 + 2 = 3
So the equation is;
y = -x + 3
