Answer:
y = -3x + 5
Expalantion:
The standard equation of a line is expressed as;
y = mx+c
m is the slope of the line
c is the intercept
Get the slope;
m = y2-y1/x2-x1
Given the coordinates (1,2) and (0,5)
m = 5-2/0-1
m = 3/-1
m = -3
Get the intercept by substituting m = -3 and any point say (1,2) into the equation
y = mx+c
2 = -3(1) + c
2 = -3 + c
c = 2+3
c = 5
The intercept is 5
Get the required equation by plugging m = -3 and c = 5 into the equation y = mx+c
y = -3x + 5
Hence the required equation is y = -3x + 5