Answer:
y =x - 3
Explanation:
Equation of a line: y = mx + b
Here, m is the slope and b is the y-intercept.
slope = m = 1
y = 1x + b
Substitute the point (2,-1) in the above equation and find 'b'.
-1 = 1*2 + b
-1 = 2 + b
-1 -2 = b
b = -3
Equation of the line: y = x - 3