Given:
[tex]y=-1-2x[/tex]If the value of x increase by 5 then the value of y is:
[tex]\begin{gathered} y=-1-2x \\ y=-1-2(x+5) \\ y=-1-2x-10 \\ y=-11-2x \end{gathered}[/tex]For decreases y is:
[tex]\begin{gathered} \text{Decrease =-1-2x-(-11-2x)} \\ =-1-2x+11+2x \\ =10 \end{gathered}[/tex]so Y is decreases by 10.
