Answer:
(a)y=-10x
(b)x=0.9
Step-by-step explanation:
If y varies directly with x, we write:
[tex]y \propto x\\y=kx$ where k is the constant of proportionality.\\If $x = -19, y = 190\\190=-19k\\$Divide both sides by -19\\k=190 \div -19\\k=-10\\[/tex]
Therefore, a direct variation equation relating y to x is:
(a)y=-10x
(b)When y=-9
Substituting y=-9 into the equation obtained in (a) above
[tex]-9=-10x\\$Divide both sides by -10$\\x=-9\div -10\\x=0.9\\$Therefore, when $ y=-9, x=0.9[/tex]
