A graph of this inequality would be a number line, with the number -2 circled (not filled in), and the number line to the right of -2 shaded.
To solve this, you will combine like terms first:
-3x-7x < 20
-10x < 20
Divide both sides by -10:
-10x/-10 < 20/-10
When you divide an inequality by a negative number, you flip the inequality symbol:
x > -2