Answer
11 is the missing number, $m=3$
Work Step by Step
If the value of x increases by 1 unit (from -1 to 0), the value of y increases by 3 units.
Therefore the value of $y$ when $x$ is $1$ is $8+3=11$
m is the change in $y$ divided by the change in $x$.
Therefore $m=3/1=3$
