Answer:
c = - 2
Step-by-step explanation:
calculate the slope m using the gradient formula
m = ( y₂ - y₁ ) / ( x₂ - x₁ )
with (x₁, y₁ ) = (8, 0) and (x₂, y₂ ) = (- 8, c)
m = [tex]\frac{c-0}{-8-8}[/tex] = [tex]\frac{c}{-16}[/tex] = [tex]\frac{1}{8}[/tex]
cross- multiplying gives
8c = - 16 ( divide both sides by 2 )
c = - 2