The equation of a line generally is written in the form y = mx + c where m is the slope and c is the y-intercept.
Equation for slope = (y2-y1)/(x2-x1)
= (-2-0)/(1-1.4) = -2/-0.4 = 5
So we get y = 5x + c
Substitute the coordinate (1,-2) in the equation to find c:
-2 = 5(1) + c
c = -2-5 = -7
Equation of line is y = 5x - 7