6. (4 + 2)·3 - (6² + 2)

Explanation:

Step1: Calculate the value inside the parentheses

$$(4 + 2)=6$$ $$6^{2}=36$$

Step2: Calculate the multiplication and division

$$6\times3 = 18$$ $$\frac{36 + 2}{6}=\frac{38}{6}=\frac{19}{3}$$

Step3: Calculate the subtraction

$$18-\frac{19}{3}=\frac{54}{3}-\frac{19}{3}=\frac{54 - 19}{3}=\frac{35}{3}$$

Answer:

$\frac{35}{3}$