Answer
$x+6=-31$
$x = -37$
Work Step by Step
We will use x as the unknown number. First we must write an equation representing the verbal sentence.
To write "the sum of a number an 6 is -31" as an equation, we need to add 6 to the number, x, and set it equal to -31. Therefore, the equation is: $x+6=-31$.
To solve, we need to subtract 6 from both sides:
$x+6 -6=-31-6$
resulting in the answer: $x = -37$.