Answer:
y is also doubled.
Step-by-step explanation:
Direct proportionality between [tex]x[/tex] and [tex]y[/tex] means that
[tex]y \propto x[/tex]
or
[tex]y=cx[/tex],
which indicates a linear relationship between [tex]x[/tex] and [tex]y[/tex] because they are related by a constant.
Therefore, if x is doubled, then the new value of [tex]y[/tex] is [tex]y_{new}[/tex]
[tex]y_{new}=c(2x)[/tex]
[tex]y_{new}=2(cx)[/tex]
[tex]y_{new}=2y[/tex]
The new value of [tex]y[/tex] is 2 times the previous; therefore, [tex]y[/tex] is doubled as [tex]x[/tex] is doubled.
