Answer:
2.
Shena should have written the associative property for step 2.
Step-by-step explanation:
1. Commutative property says [tex]a+b=b+a.[/tex] So, we can use this property to rewrite the expression [tex]3x-5+7x+6[/tex] as [tex]3x+7x+6-5[/tex]
True.
2. Associative property says [tex](a+b)+c=a+b+c+a+(b+c).[/tex] This means we can put brackets to determine convinient order of operations. Here, in step 2, Shena should use associative property to get
[tex](3x+7x)+(6-5)[/tex]
False.
3. Distributive property that [tex](a+b)\cdot c=a\cdot c+b\cdot c.[/tex] So,
[tex](3+7)x+(6-5)[/tex]
True
4. Addition property gives that [tex]3+7=10[/tex] and [tex]6-5=1,[/tex] so
[tex](3+7)x+(6-5)=10x+1[/tex]
True.