EASY ALGEBRA! HELP PLEASEEE <3 Fill in the blank with a number to make the expression a perfect square.

v²-14v+__

(fill in where the underscore is)
I know the answer is 49, But please just work out the problem!!

The volume of the sun is approximately 1 × 10^18 cu km, while the volume of jupiter is approximately 1 × 10^15 cu km. which of the following is true? a. the volume of jupiter is approximately one thousand times the volume of the sun. b. the volume of jupiter is approximately one hundred times the volume of the sun. c. the volume of the sun is approximately one thousand times the volume of jupiter. d. the volume of the sun is approximately one hundred times the volume of jupiter.