Hi, my name is Ashley. I'm in 7th grade (Pre-algebra) Student question.

I've got 2 questions. We (my dad and I) can not figure them out. please help me.

1. 21 = 9 - 2 (4a + 2) and I am supposed to find out what the variable is.
   
   
2. 2/3 n + 3/8 n = 15/16 (those are fractions). Again, I need to find out what the variable is.

Thank you very much for your help.
Sincerely,
Ashley

1. I would first work with the right side of the equation. Multiply -2 by 4a + 2 to get
   
   21 = 9 - 2 (4a + 2)
   
   21 = 9 -8a - 4
   Since 9 - 4 is 5 so this becomes
   
   21 = 5 - 8a Now, using the "balance" analogy for an equation, you can subtract 5 from both sides and maintain the balance. Thus
   
   21 - 5 = 5 - 8a - 5
   
   16 = - 8a
   Now can you find a?
   
   
2. Two-thirds of n plus three-eights of n is two-thirds plus three eights of n. That is
   
   2/3 n + 3/8 n = 15/16
   
   is
   
   (2/3 + 3/8) n = 15/16
   Add 2/3 and 3/8 by first finding a common denominator, and then see if you can find n.