#### Answer

The solution set is {x|x $\geq$ 3} , or [3, $\infty$) in interval notation.

#### Work Step by Step

We use the properties of inequalities to solve this inequality.
x $\geq$ 2.1 + 0.3x
x - 0.3x $\geq$ 2.1
0.7x $\geq$ 2.1
Divide both sides by 0.7 to obtain:
x $\geq$ 3
The solution set is {x|x $\geq$ 3} , or [3, $\infty$) in interval notation.