Complete the square for each expression. Write the resulting expression as a binomial squared

5. x^2+14x+?

6. x^2-12x+?

7. x^2-9x+?

Becca wants to mix fruit juice and soda to make a punch. she can buy fruit juice for $3 a gallon and soda for $4 a gallon. if she wants to make 28 gallons of punch at a cost of $3.25 a gallon, how many gallons of fruit juice and how many gallons of soda should she buy?