Write the perimeter of the triangle as a simplified expression.

"the product of a number and 4"
"five times the difference of a number and 3"
"the quotient of a number and 2, increased by 9 is -15"
"one-fourth of a number minus 8 is -23"
"a number is greater than -5"
"a number that is at most 30"
Which number is an integer?
Which property justifies the statement
Which set of numbers is closed under subtraction?