Originally Posted by

**Lehsyrus**

It's simple really. You have 2(a-3)+5(a+31). According to the order of operations, you must solve what is in the parenthese, then do the multiplication. Because you have a variable in the parenthese that is unknown, you have to skip to the multiplication. Now, the number being multiplied by the parenthese will have the same action against both the variable and the number inside the parenthese. Because of this, you have to distribute the number by what is inside the parenthese.

2a-6+5a+155. Now, do what you can. 7a. -6+155=149. 7a+149=?

Easy.