One of the greatest strengths of behavioral psychology is the ability to clearly observe and measure behaviors. Weaknesses of this approach include failing to address cognitive and biological processes that influence human actions.
Right away we see that expressions (a), (b), and (d) are equivalent, since addition is commutative: $2x + 8 = 8 + 2x$. We now only have to check (c) and (e). If $x=0$, (c) and (e) have the value 4, whereas (a), (b), and (d) have the value 8.So (c) and (e) are not equivalent to (a), (b), and (d).Moreover, if $x=1$, then (c) has the value 6 and (e) has the value 5, so those two expressions are not equivalent either.For (c), we can use the distributive property and decompose one of the numbers to write two equivalent expressions: $$ \begin{align} &2x+4 \\ &2(x+2) \\ &2(x+1+1) \end{align} $$.o (c) and (e) are not equivalent to (a), (b), and (d). Moreover, if $x=1$, then (c) has the value 6 and (e) has the value 5, so those two expressions are not equivalent either. For (c), we can use the distributive property and decompose one of the numbers to write two equivalent expressions:
1 The expression 3(x + y) + 7 x has two terms: 3(x + y) is the first term with a coefficient of 3; 7 x is the second term with a coefficient of 7. 2  Any expression contained in parenthesis or other grouping symbols must be treated as one term until the parentheses are removed.