Which expression is equal to (2x + 5) · 8 using the commutative property? (5 + 2x) · 8 8 · 2x + 5 · 8 2x + (5 · 8) (2x + 5 · 8) is it a?

For this case the first thing you should know is the meaning of commutative property.
 We have then that by definition:
 Commutative property: Property of certain operations that is verified when changing the order of the terms, the result remains invariable.
 Thus, an equivalent expression is:
 (2x + 5) · 8 = (5 + 2x) · 8
 
 An expression that is equal to (2x + 5) · 8 using the commutative property is:
 (5 + 2x) · 8

Do you need with the x value for the minimum? its always between the two intercepts for a parabola