Answer:
y = - x + 9
Step-by-step 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 = [tex]\frac{y_{2}-y_{1} }{x_{2}-x_{1} }[/tex]
with (x₁, y₁ ) = (0, 9) and (x₂, y₂ ) = (9, 0) ← 2 points on the line
m = [tex]\frac{0-9}{9-0}[/tex] = [tex]\frac{-9}{9}[/tex] = - 1
the line crosses the y- axis at (0, 9 ) ⇒ c = 9
y = - x + 9 ← equation of line
