Answer:
y = - 
 x
 x
Explanation:
the equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
calculate m using the slope formula
m = 

with (x₁, y₁ ) = (0, 0) and (x₂, y₂ ) = (50, - 10) ← 2 points on the line
m = 
 =
 = 
 = -
 = - 

the line crosses the y- axis at (0, 0 ) ⇒ c = 0
y = - 
 x + 0 , that is
 x + 0 , that is
y = - 
 x ← equation of line
 x ← equation of line